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Selina Concise Physics Class 7 ICSE Solutions – Heat

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Selina Concise Physics Class 7 ICSE Solutions – Heat

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for Selina Concise ICSE Solutions for Class 7 Physics. You can download the Selina Concise Physics ICSE Solutions for Class 7 with Free PDF download option. Selina Publishers Concise Physics for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

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Selina Concise ICSE Solutions for Class 7 Physics Chapter 5 Heat

  • Points to Remember
  •  Heat is a form of energy that leads to the sensations of hotness or coldness.
  •  Temperature is the degree of hotness and coldness of a body.
  •  Thermometer is used to measure temperature.
  •  The S.I. unit of temperature is °C.
  •  The most common liquid for a thermometer is mercury.
  •  The main sources of heat are (i) Fire (ii) Sun (iii) Electricity.
  •  Those substances which can easily catch fire are called inflammable substances.
  •  Those substances which are fire resistant are called non-inflammable substances.
  •  The fixed temperature at which freezing of liquid occurs is known as freezing point.
  •  The temperature at which vapourisation occurs is known as the boiling point.
  •  Substances through which heat is easily conducted are called good conductors e.g. silver, gold, copper etc.
  •  Substances through which heat is not easily conducted are called Insultors.
  •  Radiation is the process of transfer of heat from a hot body to a cold body without affecting the intermediate medium.

Test Yourself

A. Objective Questions 

1. Write true or false for each statement

(a) On touching a lump of ice, we feel cold because some heat passes from our body to the ice.
Answer. True.

(b) Heat flows from a body at a high temperature to a body at a low temperature when they are kept in contact. .
Answer. True.

(c) All solids expand by the same amount when heated to the same rise in temperature.
Answer. False.

(d) Telephone wires are kept tight between the two poles in summer.
Answer. False.

(e) Equal volumes of different liquids expand by different amounts when they are heated to the same rise in temperature.
Answer. True.

(f) Solids expand the least and gases expand the most on being heated.
Answer. True.

(g) A mercury thermometer makes use of the property of expansion of liquids on heating.
Answer. True.

(h) Kerosene contracts on heating.
Answer. False.

(i) Water is a bad conductor of heat.
Answer. True.

(j) Medium is necessary for the transfer of heat by radiation.
Answer. False.

(k) Land and sea breezes are convection currents of cold and warm air.
Answer. True.

(l) Liquids are heated by conduction and radiation.
Answer. False.

(m) Black surfaces are the poor absorbers of heat radiations.
Answer. False.

2. Fill in the blanks

(a) Heat is a form of energy.
(b) Temperature determines the degree of hotness or coldness of a body.
(c) On heating a body, its temperature rises.
(d) We use a thermometer for measuring the temperature of a body.
(e) The S.I. unit of temperature is kelvin.
(f) In a thermometer, the commonly used liquid is mercury.
(g) The temperature of a normal human body is 37 °C.
(h) A person is said to have fever if his body temperature is more than 98.6
(i) A hot metallic piece is placed in tap water contained in a bucket. Heat will flow from metallic piece to water.
(j) The temperature of boiling water is 100°C.
(k) Liquids expand more than the solids.
(l) Gases expand more than the liquids.
(m) Heat transfer in solids is by conduction.
(n) Heat transfer in liquids and gases is by convection.
(o)Metals are conductors of heat.
(p) Still air is an insulator of heat.
(q) Black and dull surfaces are good absorbers of heat.

3. Match the following

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 1

4. Select the correct alternative

(a) If we add a lump of ice to a tumbler containing water,

  1. heat flows from water to ice
  2.  heat flows from ice to water
  3.  heat flows from water to ice if water is more
  4.  heat flows from ice to water if ice is more

(b) The temperature of pure melting ice is

  1.  0°C
  2.  100°C
  3.  95°C
  4.  98.6°F

(c) A thermometer uses

  1.  water
  2. mercury
  3.  air
  4.  none of the above

(d) Which of the statement is correct

  1.  Iron rims are cooled before they are placed on cart wheels
  2.  A glass stopper gets tight on warming the neck of the bottle
  3.  Telephone wires sag in winter, but become tight in summer
  4. A little space is left between two rails on a railway track

(e) Heat in a liquid is transferred by

  1.  conduction
  2. convection
  3.  radiation
  4.  conduction and radiation

(f) In the process of convection, heat travels

  1.  sideways
  2.  downwards
  3. upwards
  4.  in all directions

(g) The vacuum kept in between the walls of a thermos flask reduces the heat transfer by

  1.  conduction only
  2.  convection only
  3.  radiation only
  4. conduction and convection

B. Short/Long Answer Questions

Question 1.
What is heat ? State its S.I. unit.
Answer:
Heat is a form of energy which flows. It is the energy of motion of molecules constituting the body.
The unit of heat is same as that of energy, The S.I. unit of heat is joule (abbreviated as J) and other common units of heat are calorie and kilo calorie, where 1 k cal = 1000 cal.

Question 2.
What is meant by the term temperature.
Answer:
Temperature is a quantity which tells the thermal state of a body (i.e. the degree of hotness or coldness). It determines the direction of flow of heat when the two bodies at different temperatures are placed in contact.

Question 3.
State the three units of temperature.
Answer:
The S.I. unit of temperature is kelvin or K. The other most common unit of temperature is degree Celsius (°C) and degree Fahrenheit (°F).

Question 4.
Name the instrument used to measure the temperature of a body.
Answer:
To measure the temperature of a body with the help of a thermometer.

Question 5.
Name two scales of temperature. How are they inter-related?
Answer:
Two scales of temperature are
(i) Celsius (ii) Fahrenheit
Relation:

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 2

Question 6.
How is the size of a degree defined on a Celsius scale ?
Answer:
The interval between the ice point and steam point divided by 100 (hundred) equal parts is called a degree on the Celsius scale.

Question 7.
How is the size of a degree defined on a Fahrenheit scale?
Answer:
The interval between the ice point and steam point divided into 180 equal parts is called a degree on the Fahrenheit scale.

Question 8.
State the temperature of (i) ice point and (ii) steam point, on the Celsius scale.
Answer:
(i) Ice point. Is the the mark on Celsius scale at which ice melts. Ice point on the Celsius scale is 0°C.
(ii) Steam point. On the Celsius scale is the mark at which water changes into steam at normal atmospheric pressure. On Celsius scale it is 100°C.

Question 9.
Write down the temperature of (i) lower fixed point, and (ii) upper fixed point, on the Fahrenheit scale.
Answer:
Lower fixed point: On the Falirenheit scale is the mark at which pure ice melts. It is 32°F on Fahrenheit scale.
Upper fixed point: On the Fahrenheit scale is the mark at which water starts changing into steam at normal atmospheric pressure. It is 212°F.

Question 10.
What is the Celsius scale of temperature ?
Answer:
Celsius scale is that which has ice point as 0°C and steam point marked as 100°C.

Question 11.
What is the Fahrenheit scale of temperature ?
Answer:
Fahrenheit scale is that which has ice point as 32°F and the steam point marked as 100°C.

Question 12.
What is the Kelvin scale of temperature ?
Answer:
On Kelvin scale of temperature zero mark is when no molecular motion occurs. Ice point is at 273 and steam point is at 373 K. Thus 0 K = – 273°C and one degree on Kelvin scale is same as one degree on Celsius scale.

Question 13.
The fig. shows a glass tumbler containing hot milk which is placed in a tub of cold water. State the direction in which heat will flow.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 3
Answer:
When we bring two objects of different temperature together, energy will always be transferred from hotter to the cooler object.
Here, also heat will flow from hot milk tumbler to tub of cold water.

Question 14.
Draw a neat labelled diagram of a laboratory thermometer.
Answer:

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 4

Question 15.
Write down the body temperature of a healthy person.
Answer:
The temperature of a healthy persons is 98.6 degrees fahrenheit or 37.0 degree Celsius or 310 k.

Question 16.
What do you understand by thermal expansion of a substance ?
Answer:
The expansion of a substance when, heated, is called thermal expansion.
Or
Thermal expansion is the tendency of matter to change .in shape, area and volume in response to a change in temperature.

Question 17.
Name two substances which expand on heating.
Answer:
Mercury and Aluminium wire.

Question 18.
Why do telephone wires sag in summer ?
Answer:
The telephone wires will sag in summer due to expansions and will break in winter due to contraction.
Therefore, while putting up the wires between the poles, care is taken that in summer they are kept slightly loose so that they may not break in winter due to contraction.
While in winter they are kept light so that they may not sag too much in summer due to expansion.

Question 19.
Iron rims are heated before they are fixed on the wooden wheels. Explain the reason.
Answer:
The wooden wheels of a bullock-cart are fitted with iron tyres. To ensure a tight fit, the tyre is made slightly smaller in diameter than the wheel. The tyre is first heated due to which it expands. The heated tyre is then fitted on the wheel. When the tyre cools, it contracts and makes a tight fit on the wheel.

Question 20.
Why are gaps left between successive rails on a railway track ?
Answer:
The rails of railway track are made of steel. While laying the railway track, a small gap is left between the two successive length of rails. The reason is that the rails expand in summer. The gap is provided to allow for this expansion. If no gap is left, the expansion in summer will cause the rails to bend sideways. This may result in a train accidents.

Question 21.
A glass stopper stuck in the neck of a bottle can be removed by pouring hot water on the neck of the bottle. Explain why ?
Answer:
When hot water is poured over the neck of the bottle, it expands. As a result the stopper gets loosened and can be removed easily.

Question 22.
Why is a cement floor laid in small pieces with gaps in between?
Answer:
The floor is laid in small pieces with gaps in between to allow for the expansion during summer. However glass strips can be placed in the gaps.

Question 23.
One end of a steel girder in a bridge is not fixed, but is kept on roliers. Give the reason.
Answer:
In the construction of a bridge, steel girders are used. One end of the girder is fixed into the concrete or brick pillars and its other end is not fixed, but it is placed on rollers. The reason is that if there is any rise (or fall) in temperature of atmosphere, the girder can freely expand (or contract) without affecting the pillars.

Question 24.
Describe one experiment to show that liquids expand on heating.
Answer:
(i) Take an empty bottle with a tight fitting cork having a hole drilled in its middle, a drinking straw, two bricks, a wire guaze and a burner.
(ii) Fill the bottle completely with water and add few drops of ink in it to make it coloured.
(iii) Fix the cork in the mouth of the bottle and pass the drinking straw through the cork. Put some molten wax around the hole so as to avoid the leakage of water.
(iv) Pour some more water into the drinking straw so that water level in the straw can be seen. Mark the water level in the straw as shown in Figure.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 5
(v) Place the bottle on the wire gauze kept over the two bricks as shown in Figure. Then heat the bottle by means of a burner.
(vi) Look at the level of water in the straw.
You will notice that as the water is heated more and more, the level of water in the drinking straw rises. This shows that water expands on heating.

Question 25.
State one application of thermal expansion of liquids.
Answer:
Mercury is a metal found in liquid state. It expands more and uniformly over a wide range of temperature. So mercury is used as thermometric liquid.

Question 26.
Describe an experiment to show that air expands on heating.
Answer:
(i) Take an empty bottle. Actually the empty bottle contains air. Attach a rubber balloon to its neck as shown in Figure. Initially, the balloon is deflated.
(ii) Place the bottle in a water bath containing boiling water. After some time you will notice that the balloon gets inflated as shown in Figure. The reason is that the air inside the bottle expands on heating and it fills the balloon.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 6
(iii) Take the bottle out of the water bath and 7 allow it to cool by itself. We will notice that the balloon gets deflated and it collapses. This is because the air inside the balloon and the bottle, has contracted on cooling. The air from balloon passes to the bottle, so the balloon gets deflated.

Question 27.
An empty glass bottle is fitted with a narrow tube at its mouth. The open end of the tube is kept in a beaker containing water. When the bottle is heated, bubbles of air are seen escaping into the water. Explain the reason.
Answer:
When the bottle is heated, bubbles of air are seen escaping into the water. This happens because the air present in glass bottle expands on heating and tries to escape out through the tube into the water.

Question 28.
State which expands more, when heated to the same temperature : solid, liquid or gas ?
Answer:
Gases expand much more than the liquids and the solids. Like liquids, the gases do not have a definite shape, so they also have only the cubical expansion.

Question 29.
Name the three modes of transfer of heat.
Answer:
There are three modes of transfer of heat (i) Conduction (ii) Convection (iii) Radiation.
(i) Conduction “is that mode of transfer of heat, when heat travels from hot end to cold end from particle to particle of the medium, without actual movement of particles.”
(ii) Convection. “Is a process of transfer of heat by actual move-ment of the medium particles.”
(iii) Radiation. “Is that mode of transfer of heat in which heat directly passes from one body to the other body without heating the medium.”

Question 30.
Name the mode of transfer of heat in the following :
(a) solid,
(b) liquid,
(c) gas
(d) vacuum
Answer:

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 7

Question 31.
What are the good and bad conductors of heat ? Give two examples of each.
Answer:
Good conductors. “The substances through which heat is easily conducted are called good conductors of heat.”
Example : Copper, iron.
Bad conductors. “The substances through which heat is not conducted easily are called bad conductors of heat or poor conductors of heat.”
Example : Wood, cloth.

Question 32.
Name a liquid which is a good conductor of heat.
Answer:
Mercury is good conductor of heat.

Question 33.
Name a solid which is a good conductor of heat.
Answer:
Aluminium is a good conductor of heat.

Question 34.
Select good and bad conductors of heat from the following :
copper, mercury, wood, iron, air, saw-dust, cardboard, silver, plastic, wool.
Answer:
Good conductors — Mercury, copper, silver, iron.
Bad conductors — Wood, air, saw dust, plastic, wool, cardboard.

Question 35.
Why is an oven made of double walls with the space in between filled with cork ?
Answer:
An oven is made of double walls and the space between them is filled with wool, cork etc. because the wool and cork are the insulator of heat. They prevent the heat of the oven to escape.

Question 36.
Why do we use cooking utensils made up of copper.
Answer:
Cooking utensils are made of metals such as copper, aluminium, brass, steel etc., so that heat is easily conducted through the base to their contents. But they are provided with handles of bad conductors (such as ebonite or wood) to hold them easily as handles will not conduct heat from the utensil to our hand.

Question 37.
Why is a tea kettle provided with an ebonite handle ?
Answer:
Tea kettles are provided with wooden or ebonite handles. The wood or the ebonite being the insulators of heat, does not pass heat from the utensils to our hand. Thus, we can hold the hot utensils or pans comfortably by their handles.

Question 38.
In summer, ice is kept wrapped in a gunny bag. Explain the reason.
Answer:
In summer, the ice is kept wrapped in a gunny bag or it is covered with saw dust. The air filled in the fine pores of the gunny bag or saw dust, is the insulator of heat. The air does not allow heat from outside to pass through it to the ice. Thus, the ice is prevented from melting rapidly.

Question 39.
Explain why
(a) we wear woolen clothes in winter.
(b) the water pipes are covered with cotton during very cold weather.
Answer:
(a) Woolen clothes have fine pores filled with air. Wool and air both are bad conductors of heat. Therefore in winter, we wear woolen clothes as they check the conduction of heat from the body to the surroundings and thus keeps the body warm.
(b) During very cold weather, the water pipes are covered with cotton. The cotton has air trapped in its fine pores. The cotton and air are the insulators of heat. They do not pass heat from water inside the pipes to the outside atmosphere. Thus, cotton prevents the water in the pipes from freezing.

Question 40.
Why are quilts filled with fluffy cotton ?
Answer:
Quilts are filled with fluffy cotton. Air is trapped in the fine pores of cotton. Cotton and air are the insulators of heat. They check heat from our body to escape and thus keep us warm.
The newly made quilts are warmer than the old ones because in the old quilts, there is no air trapped in the cotton.

Question 41.
State the direction of heat transfer by way of convection.
Answer:
By the process of convection, heat is always transferred vertically upwards. The reason is that the medium particles near the source of heat absorb heat from the source and they start moving faster. As a result, the medium at this place becomes less dense so it rises up and the medium from above being denser, moves down to take its place. Thus, current is set up in the medium which is called a convection current. The current continues till the entire medium acquires the same temperature.

Question 42.
Why is a ventilator provided in a room ?
Answer:
Ventilators and windows are provided in rooms for proper ventilation. The reason is that when we breathe out in a room, the air in the room becomes warm and impure. The warm air is less dense i.e. lighter, so it rises up and moves out through the ventilators. Then the cold fresh air comes in the room through the windows to take its place. Thus the continuous circulation of fresh air keeps the air in the room fresh.

Question 43.
Why are chimneys provided over furnace in factories ?
Answer:
Chimneys are provided over the furnace in factories. This is because the hot gases coming out of the furnace are less dense than the air. They rise up through the chimney. The smoke, fumes etc. around the furnace rush in so as to take their place and they are sucked out. Thus, the chimney helps to remove the undesired fumes, smoke etc. from the premises.

Question 44.
What are the land and sea breezes ? Explain their formation.
Answer:
LAND BREEZE : Blowing of breeze (air) from land towards sea is called land breeze.
During night land and sea water both lose heat. Specific heat capacity of land being very low as compared to that of sea water, land loses heat energy fast and cools more rapidly as compared to sea. Sea water being at higher temperature, the air above it becomes lighter and rise up. Air from land being at higher pressure. So air from land starts blowing towards sea and gives rise to Land Breeze.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 8
SEA BREEZE : Blowing of breeze (cold air) from sea towards land during the day is called the SEA BREEZE. During day time land and sea both are heated equally by the sun, but land has very low specific heat capacity as compared to sea, is heated up more quickly. Thus air above land due to heat becomes lighter and rises up. Thus pressure decreases and cold and humid air above the sea starts blowing towards land, thereby giving rise to SEABREEZE.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 9

Question 45.
Why is the freezing chest in a refrigerator fitted near its top?
Answer:
Freezing chest in a refrigerator is fitted near the top, because it cools the remaining space of the refrigerator by convection current. Air near the top comes in contact with the freezing chest gets cooled, becomes denser and therefore descends while the hot air from the lower part rises and hence convection currents produced cool the whole space inside.

Question 46.
Explain briefly the process of heat transfer by radiation.
Answer:
RADIATION. “The transfer of heat energy from a hot body to cold body directly, without heating the medium between two bodies is called RADIATION.”
The radiant heat or thermal radiation is of the form of ELECTROMAGNETIC WAVES. These waves can travel even in vacuum in all directions in straight line with the speed of light. They do not heat the medium through which they pass. Heat radiations are also called INFRA-RED RADIATIONS because the wavelength of heat radiations is longer than that of visible light. These radiations can cause heating effect only if they are absorbed by some material.

Question 47.
Give one example of heat transfer by radiation.
Answer:
When we sit in the sun, we feel warm. We cannot get heat from the sun by the process of conduction or convection because most of the space between the sun and the earth is a vacuum and both of these modes of heat transfer require medium. Hence, one must be getting heat from the sun by the mode of radiation.

Question 48.
Why do we prefer to wear white or light coloured clothes in summer and black or dark coloured clothes in winter ?
Answer:
We prefer to wear white clothes in summer. The reason is that the white clothes reflects most of the sun’s heat and absorb very little of the sun’s heat, thus they keep our body cool.
We prefer to wear black and dark coloured clothes in winter. The reason is that the black or dark colour clothes absorb most of the sun’s heat and keep our body warm.

Question 49.
The bottom of a cooking utensil is painted black. Give the reason.
Answer:
The bottom part of the cooking utensil or pan is painted black. The reason is that the black surface absorbs more heat and so the contents of utensil or pan get cooked rapidly if its bottom part is painted black.

Question 50.
Draw a labelled diagram of a thermo flask. Explain how the transfer of heat by conduction, convection and radiation is reduced to a minimum in it.
Answer:
Heat transfer is minimised because of:
(1) The vacuum between the two walls, rubber, glass, cork and air do not allow the loss of heat by conduction.
(2) Cork in the neck of flask and the cup over it prevent loss of heat by convection.
(3) Heat cannot be lost by conduction or convection because of vacuum between the two walls.
(4) Heat loss is also minimised by radiation, by making outer surface of inner wall and inner surface of outer wall silvered. The inner wall is a BAD RADIATOR and the outer wall is a GOOD REFLECTOR of radiation.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 10

C. Numericals

Question 1.
The temperature of a body rises by 1°C. What is the corresponding rise on the (a) Fahrenheit scale (b) Kelvin scale?
Answer:
(a) Since 100 divisions on Celsius scale =180 divisions on the Fahrenheit scale 1 division on Celsius scale
∴ 1 division on Celsius scale
= 1.80 / 1.00 × 1
= 1.8 divisions in the Fahrenheit scale.
For 1°C rise corresponding rise in Fahrenheit = 1.8°F
(b) Since 100 divisions in the Celsius scale = 100 divisions in the Kelvin scale
1 division on Celsius scale = 100 / 100 × 1
= 1 division on Kelvin scale
For 1°C rise corresponding rise in Kelvin is 1 K.

Question 2.
The temperature rises by 18°F. What is the rise on the Celsius scale ?
Answer:
Since 100 divisions on the Celsius scale =180 divisions on the Fahrenheit scale
∴ 18 divisions on Fahrenheit scale.

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 11

Question 3.
Convert 5°F to the Celsius scale.
Answer:

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 12

Question 4.
Convert 40°C to the (a) Fahrenheit scale (b) Kelvin Scale.
Answer:
(a) Fahrenheit scale
C = 40°C
Substitute value of C = 40° in below equation

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 13

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 14

Question 5.
Convert – 40°F to the Celsius scale.
Answer:

Selina Concise Physics Class 7 ICSE Solutions Chapter 5 Heat 15

ICSE Solutions for Class 8 History and Civics – India in the Eighteenth Century

by

ICSE Solutions for Class 8 History and Civics – India in the Eighteenth Century

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 8 History and Civics. You can download the History and Civics ICSE Solutions for Class 8 with Free PDF download option. History and Civics for Class 8 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 8 History & Civics GeographyBiologyChemistryPhysicsMaths

Time To Learn
I. Fill in the blanks:

  1. Murshid Quli Khan became the independent ruler of Bengal and shifted his capital to Murshidabad.
  2. Chin Qilich Khan founded the Asaf Jahi dynasty in AD 1724.
  3. Haider Ali was the ruler of Mysore.
  4. Banda Bahadur was the leader of the Sikhs after the death of Guru Govind Singh.
  5. Balaji Vishwanath was the first Peshwa.

II. Match the contents of Column A and Column B:
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 1
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 2

Answer:
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 3

III. State whether the following statements are True or False:

  1. The office of the Peshwas was always hereditary.
    False.
  2. In the Third Battle of Panipat, the Marathas fought with the Rajputs and the Jats.
    False.
  3. The later Mughal kings were able rulers.
    False.
  4. Safdar Jung was the first Nizam of Hyderabad.
    False.
  5. Jai Singh built an observatory (Jantar Mantar) and Pink City (Jaipur).
    True.

 IV. Answer the following questions:

Question 1.
Write in brief the causes that led to the downfall of the Mughal empire.
Answer:
Causes that led to the downfall of Mughal Empire were
(a)
Weak successors: After Aurangzeb’s death the Mugh empire started declining. His successors were weak are were toys in the hands of nobles and Governors. The lacked the administrative skills of their predecessors.
(b)
Internal Rivalry: The nobles and Governors belonged different groups and were always engaged in const? struggle for power. This hampered the growth of the emp
(c)
Crisis in Jagirdari and Mansabdari system: The Mugh introduced the Jagirdari and the mansabdari systems , smooth running of their administration but they only prov to be the cause of the decline of their empire.
(d)
Invasion of Nadir Shah and Ahmad Shah Abdali: Duri the reign of Mohammad Shah two foreign invasions crippl the Mughal empire. They invaded India and weakened tl Mughal Empire.

Question 2.
When and between whom was the Third Battle of Panipa fought? What were its results?
Answer:
The third battle of Panipat was fought in 1761 between Ahmad Shah Abdali, an Afghan invader and Peshwa Balaji Baji Rao. The Peshwa suffered a crushing defeat and this put an end to the Maratha power.

Question 3.
Name the first independent Nawab of Bengal. What were his achievements?
Answer:
Murshid Quli Khan became the first independent Nawab of Bengal. He established an efficient administration and effectively organised the revenue system. He also started the new system of land revenue collection, on the basis of contracts, known as Ijara system. He reorganised the zamindari for which he is will remembered in the history of Bengal.

Question 4.
When was the Battle of Plassey fought? What effect did it have on the position of the English East India Company?
Answer:
The Battle of Plassey was fought in 1757 between the British and Siraj-ud-daulah in which the English defeated the army of Siraj-ud-daulah. From then onwards the English East India Company functioned as king makers in Bengal politics. Finally,the English established their full sway in 1765 when Robert Clive set up the Dual Government in Bengal.

Question 5.
Who was Haider All? Discuss his achievements.
Answer:
Hyder All was the ruler of Mysore. He started his career as an ordinary soldier in the Mysore army. He won many battles against the Marathas, the Nizam of Hyderabad and routed his enemies in two consecutive Anglo-Mysore Wars.

Question 6.
Which ruler was known as the Tiger of Mysore?
Answer:
Tipu Sultan, the son and heir of Haider Ah and ruler of Mysore is known as ‘Tiger of Mysore.

V. Tell me why

Question 1.
The consequence of the Third Battle of Panipat was n advantageous for the British.
Answer:
The Marathas had established a Maratha Kingdom during the reign of Aurangzeb. They were very powerful and with time and with the decline of the Mughals would have proved worthy , opponents to the emerging British empire but the third Battle of Panipat (1761) sealed their fate. Ahmad Shah Abdali, an Afghan . invader gave a crushing defeat to the forces of Peshwa Balaji Baji Rao. It put an end to the Maratha power and their dream of ruling India. Thus, the way was proved for the British East India Company to gain power and become supreme.

Question 2.
Independent states were formed in the 18th century.
Answer:
The later Mughal rulers were so weak that they could not hold the provinces of the empire together. These provinces were under Governors who were always engaged in wars. Gradually, they took advantage of the situation of misrule and misgovemance by the central authority and declared independence.Thus, Bengal, Hyderabad, Awadh Rohikhand became independent one after the other.

VI. Pictury study – This is a picture of a great ruler of Punjab.
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 4

Question 1.
Identify him.
Answer:
Maharaja Ranjit Singh.

Question 2.
How did the unite the Sikhs in Punjab?
Answer:
Maharaja Ranjit Singh brought the whole area west of River Sutlej under his control and established the Sikh kingdom in Punjab. He signed the Treaty of Amritsar (1809) with the British which confirmed his conquests and established his sovereignty over the terrioty west of Satluj. It was only after his death in 1839 that the British gained control over the Punjab.

Additional Questions

EXERCISES
A. Fill in the blanks:

  1. During the first half of the 18th century, the great Mughal empire decayed and disintegrated.
    The Mughal emperors who ruled India after the death of Aurangzeb are known as the later Mughals.
  2. There were four groups of nobles in the Mughal court.
  3. Nadir Shah looted and plundered Delhi He carried away immense treasures including the priceless Kohinoor and the Peacock Throne.
  4. Ahmad Shah Abdali, the ruler of Afghanistan, repeatedly attacked the Mughal empire.
  5. Bahadur Shah Zafar, was defeated in the Revolt of 1857 and exiled to Rangoon by the British.

B. Match the following:
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 5
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 6
Answer:
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 7

C. Choose the correct answer:

  1. Aurangzeb/Akbar/Shah Jahan followed a policy of religious intolerance.
    Ans. Aurangzeb followed a policy of religious intolerance.
  2. The military campaign in the Deccan led by Shah Jahan/ Aurangzeb/Akbar ruined the Mughal empire financially
    Ans. The military campaign in the Deccan led by Aurangzeb ruined the Mughal empire financially.
  3. The invasions of Ahmad Shah Abdali, the ruler of Afghanistan/Persia/Iraq shattered the power and prestige of the Mughal empire.
    Ans. The invasions of Ahmad Shah Abdali, the ruler of Afghanistan shattered the power and prestige of the Mughal empire.
  4. The Mughal empire lasted for over 3/5/6
    Ans. The Mughal empire lasted for over 3 centuries.
  5. The British ruled over India for a 100 years/nearly 200 years/ 300 years.
    Ans. The British ruled over India for nearly 200 years.

D. State whether the following are true or false.

  1. Bahadur Shah ascended the throne after the death of Aurangzeb.
    True.
  2. The Mughal court was united and stable.
    False
    Correct:- The Mughal court was divided and unstable.
  3. The Mughal officers were given jagirs as payments for their services.
    True.
  4. The Mughal rulers did not have a navy.
    True.
  5. The successors of Aurangzeb were very strong and efficient.
    False.
    Correct: The successors of Aurangzeb were very weak and unefficient.

E. Answer the following questions in one or two words/ sentences:

Question 1.
When did the transition from the Medieval to the Modern Period begin in India?
Answer:
The transition from the Medieval to the Modem Priod began with the decline of the Mughal empire in the first half of the 18th century.

Question 2.
Name the first and the last emperors in the line of the Later Mughals.
Answer:
Bahadur Shah first in the line of emperors referred to as the Later Mughals. Bahadur Shah Zafar last emperor in the line of the Later Mughals.

Question 3.
Name any two rival groups of nobles in the Mughal court.
Answer:

  1. The Iranis hailed from Persia
  2. Turanis hailed fromTransoxiana.

Question 4.
Mention any two reasons for the failure of the mansabdari system.
Answer:
Mansabdars had to maintain a fixed number of troops. They were given jagirs as the payment for doing so. Later, an increase in the number of mansabs and a shortage of jagirs led to corruption and inefficiency in the system.

Question 5.
What was the economic impact of the Mughal wars of succession?
Answer:
After the death of a Mughal ruler, generally there were wars of succession among rival claimants to the throne. These wars proved very costly and destructive. They drained the resources of the empire and made it instable and weak.

Question 6.
How did Aurangzeb’s religious policy affect the relationship between the Mughals and the Rajputs?
Answer:
Aurangzeb’s policy of religious intolerance shook the foundations of the empire and resulted in the following:

  • The costly, long-drawn and ruinous Deccan campaign.
  • Numerous wars with the Sikhs, the Marathas, the Jats and the Rajputs.
  • Loss of support of the loyal Rajputs who had earlier contributed greatly to the stability of the Mughal empire but now became its bitter foes.

Question 7.
What led to the drain on the royal treasury during Shah Jahan’s reign?
Answer:
The enormous sums of money spent by Shah Jahan on magnificent monuments like the Taj Mahal had drained the royal treasury.

Question 8.
Which Mughal emperor assumed leadership of the Revolt of 1857? What happened to him after the Revolt?
Answer:
Bahadur Shah Zafar, the last of the Mughals, assumed leadership of the rebels in the Revolt of 1857 against the British. He was defeated and exiled to Rangoon where he died. The Mughal empire came to an inglorious end.

F. Answer the following questions briefly.

Question 1.
Several factors were responsible for the decline of the Mughal empire. In this context answer the following questions:
(a).How did court politics undermine the authority and prestige of the Mughal empire?
(b).To what extent was the jagirdari crisis responsible for a further decline of the power of the emperor?(c).How did the wars of succession destabilize the Mughal empire?
Answer:
(a).
There were four groups of nobles in the Mughal court- Iranis, Turanis, Afghans and Hindustanis. The Iranis hailed from Persia, the Turanis hailed from Transoxiana, and the Afghans came from the mountainous border regions across the river Indus. The Mughal court was a house sharply divided from within. This resulted in a constant struggle for power among these groups. Their mutual jealousies and rivalries caused great harm to the Mughal administration and undermined the prestige and authority of the Mughal emperor.
(b)
The Mughal officers were given jagirs as payment for their services. Towards the end of the 17th century, there were very few jagirs left. To satisfy the demands of the newly recruited officers, crown lands were converted to jagir lands and given to the nobles. This led to a loss of revenue for the royal treasury and a further decline in the power of the emperor.
(c)
After the death of a Mughal ruler, generally there were wars of succession among rival claimants to the throne. These wars proved very costly and destructive. They drained the resources of the empire and made it instable and weak.

Question 2.
With reference to the decline and disintegration of
(a) The Mughal empire discuss the following:
(b) The breakdown of the mansabdari system The weaknesses
(c) of the Mughal army Aurangzeb’s religioius policy
Answer:
(a) Under this system, mansabdars had to maintain a fixed number of troops. They were given jagirs as the payment for doing so. Later, an increase in the number of mansabs and a shortage of jagirs led to corruption and inefficiency in the system.

(b) The Mughal army also failed to keep pace with the time. The Mughal rulers did not have a navy and made no efforts to establish one. Their equipment and techniques of warfare were obsolete and ineffective. Nothing was done to reform, modernize and strengthen the army.

(c) His policy of religious intolerance shook the foundations of the empire and resulted in the following:

  1. The costly, long-drawn and ruinous Deccan campaign.
  2. Numerous wars with the Sikhs, the Marathas, the Jats and the Rajputs.
  3. Loss of support of the loyal Rajputs who had earlier contributed greatly to the stability of the Mughal empire but now became its bitter foes.

Question 3.
To what extent were the following factors responsible for the eventual collapse of the Mughal empire?
(a) Economic bankruptcy (b) Foreign invasions (c) Weak successors
Answer:
(a) Economic bankruptcy: A major cause of the disintegration of the Mughal empire was its economic bankruptcy. The enormous sums of money spent by Shah jahan on magnificent monuments like the Taj Mahal had drained the royal treasury. Aurangzeb’s Deccan campaign was a financial disaster that ruined the empire and made its collapse inevitable.

(b)Foreign invasions: The invasions of Nadir Shah, the ruler of Persia (Iran), and Ahmad Shah Abdali, the ruler of Afghanistan, shattered the power and prestige of the Mughals. Nadir Shah looted and plundered Delhi and carried away valuable treasures, including the priceless Kohinoor Diamond and the Peacock Throne. Ahmad Shad Abdali plundered northern India repeatedly.

(c) Weak successors: Aurangzeb ruled over a vast empire which he controlled with an iron hand. His successors were pleasure-loving, weak and inefficient. They were puppets in the hands of powerful, ambitious nobles who controlled the administration. The provincial governors took advantage of the weak government at the centre and set up independent kingdoms in the Mughal provinces. This led to the break-up and collapse of the empire.

G. Picture Study:

This is a portrait of the last of the Later Mughals.
ICSE Solutions for Class 8 History and Civics - India in the Eighteenth Century 8

Question 1.
Identify the Mughal emperor represented in this picture.
Answer:
Bahadur Shah Zafar.

Question 2.
What part did he play in the Revolt of 1857?
Answer:
Role of Bahadur Shah Zafar in the Revolt of 1857:
As the Indian rebellion of 1857 spread, sepoy regiments seized Delhi. Seeking a figure that could unite all Indians, Hindu and Muslim alike, Most rebelling Indian kings and the Indian regiments accepted Zafar as the Emperorof India. Under whom the smaller Indian kingdom would unite until the British were defeated. Zafar was the least threatening and least ambitious of monarchs, and the legacy of the Mughal Empire was more acceptable a uniting force to most allied kings than the domination of any other Indian kingdom.

Question 3.
What happened to the Mughal empire after his death?
Answer:
The Mughal Empire came to an inglorious end.

Question 4.
Mention any four reasons for the decline of the Mughal empire Explain any two reasons.
Answer:
(a) Politics in the Mughal court
(b) Weak Military organization and Administration
(c) Aurangzeb’s Bankruptcy
(d) Foreign Invasions

  • Politics in the Mughal court: There were four groups of nobles in the Mughal court Iranis, Turanis, Afghans and Hindustanis. The Iranis hailed from Persia, the Turanis hailed from Transoxiana, and Afghans came from the mountainous border regions across the Indus. The Mughal court was a house sharply divided from within. This resulted in a constant struggle for power among these groups. Their mutual jealousies and rivalries caused great harm to the Mughal administration and undermined the prestige and authority of the Mughal Emperor.
  • Economic Bankruptcy: A major cause of the disintegration of the Mughal Empire was its economic bankruptcy. The enormous sums of money spent by Shah Jahan on magnificent monuments like the Taj Mahal had drained the royal treasury. Aurangzeb’s Deccan campaign was a financial disaster that ruined the empire and made its collapse inevitable.

ICSE Solutions for Class 6 Geography Voyage – North America : Location, Area, Political and Physical Features

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ICSE Solutions for Class 6 Geography Voyage – North America : Location, Area, Political and Physical Features

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 6 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 6 with Free PDF download option. Geography Voyage for Class 6 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 6 GeographyHistory & CivicsBiologyChemistryPhysicsMaths

POINTS TO REMEMBER

  • North America has been named after Amerigo Vespucci, an Italian explorer. However, Christopher Columbus is credited with the discovery of this continent.
  • The continent lies in the northern and the western hemispheres surrounded by the Arctic, the Atlantic and the Pacific oceans. The Isthmus of Panama joins North America to South America.
  • The United States of America and Canada occupy three fourths of North america.
  • NorthAmerica can be divided into four major physical divisions— the Canadian or Laurentian Shield, the Western Mountain System or Western Cordilleras, the Eastern Highlands or Appalachian Mountains and the Central Lowlands or Great Central Plains.
  • The Canadian Shield is composed of some of the oldest known hard rocks of the world. The surface of the Shield consists of many deep depressions formed by scraping and scouring out by moving ice. These depressions have been filled up with meltwater to form many freshwater lakes such as the five Great Lakes.
  • The Western Cordilleras are a series of young fold mountain ranges which have many active and extinct volcanoes, earthquake-prone regions and hot springs. The Cordilleras consist of several parallel ranges such as the Alaska Range and the Brooks Range. The highest point in North America, Mt McKinley, lies here. .
  • The Appalachians are lower than the Western Cordilleras. The eastern slopes of these highlands are very steep.
  • The edge of the Piedmont Plateau (located at the foot of the Appalachians or the Eastern Highlands) has many waterfalls along its length. It is referred to as the Fall Line.
  • The Great Central Plains have the largest river system in North America—the Mississippi-Missouri river system.
  • North America has several large rivers such as the Mississippi, Missouri, Mackenzie, Nelson, St Lawrence, Hudson, Yukon, Columbia and Rio Grande.
  • Lumbering is an important activity in the coniferous or taiga forests of Canada, carried out by lumbermen or lumberjacks.
  • Lumbering involves several stages of work such as cutting, skidding and hauling.

IMPORTANT TERMS

Gorge : A deep narrow valley with near vertical sides. Intermontane plateau: a plateau surrounded by mountains on all sides.
Lumbering : The cutting down of trees and the processes leading to the manufacture of products like paper, newsprint, synthetic fibres, etc.
Lumberjacks : Workers engaged in lumbering.
Meltwater : Water derived from the melting of glacier ice and/or snow.

VALUES AND LIFE SKILLS

All occupations are important. Every job has dignity and deserves our respect.
How do you treat the people who work in your home and help you in your daily life ?
Answer:
We treat them with respect and dignity.

EXERCISES

A. Fill in the blanks

  1. A narrow stretch of land that joins North America to South America and separates the Atlantic Ocean from the Pacific Ocean : The Isthmus of Panama.
  2. The tropical islands, called the West Indies, are located in this sea : Caribbean Sea.
  3. Aphysical division of North America around the Hudson Bay which has the oldest known hard rocks of the world : The Canadian Shield.
  4. A river that flows northwards and drains into the Hudson Bay : River Meckenzie and River Nelson.

B. Identify who I am.

  1. I am a city in North America which is a symbol of unity, history, and democracy : Washington DG.
  2. I am an island at the entrance of river Hudson where the famous Statue of Liberty is situated : Liberty Island.
  3. I am the city which is world famous for its film industry : Los Angeles.
  4. I am the city which has the Ridean Canal : Ottawa
  5. I am the city of Canada which was once the world’s leading grain port : Montreal

C. Give geographical reasons why 

Question 1.
The 49° N latitude and the 100°W longitude are important for North America.
Answer:
The 49° N latitude marks the boundary between Canada and United States whereas 100°W longitude passes through the centre of North America. So both are important.

Question 2.
The Western Cordilleras form part of the ‘Pacific Ring of Fire’.
Answer:
The Western Cordilleras i.e. the western part of North America from Alaska to the Isthmus of Panama consists of young fold mountain ranges which contain very active volcanoes and lie close to the pacific ocean thus forming a part of the ‘ Pacific Ring of Fire’.

Question 3.
The Appalachians appear as low hills today.
Answer:
The Appalachians are old fold mountains and the glaciers and rivers have eroded them over millions of years. So they appear as low hills today.

Question 4.
Lumbering is traditionally done in the winter season.
Answer:
In winters the sap in trees is frozen,making it easier to cut and drag the logs on frozen river grounds. The winter air is clean, refreshing and free from perts.

D. Answer the following questions in brief
Question 1.
Name the Italian explorer who reached North America in 1507 CE.
Answer:
Amerigo Vespucci.

Question 2.
Name some of the islands that are collectively called the West Indies.
Answer:
The tropical islands of the Caribbean sea are collectively called the West Indies. They include Cuba, Jamaica, Puerto Rico, Dominican Republic, Haiti, etc. form West Indies.

Question 3.
Why is New York an important city in the USA ?
Answer:
Hudson River is the famous Statue of Liberty on Liberty Island.

Question 4.
Where are the Great Lakes situated ? Which river drains these lakes into the Atlantic Ocean ?
Answer:
The Great Rivers are located in the Canadian or Laurentian shield. The St. Lawrence River connects and drains the Great Lakes.

Question 5.
Write about the largest river system of North America.
Answer:
The largest river system of America includes River Mackenzie falling into the Arctic Ocean. St. Lawrence, Hudson connecting all the Great Lakes draining into the North Atlantic Ocean, Yukon, Columbia falling into Pacific Ocean and Mississippi and Missouri rivers falling into Gulf of Mexico.

Question 6.
Where is the Grand Canyon situated ? Why is it so famous?
Answer:
The Grand Canyon of the Colorado River is 2000 m deep and 400 km long and so it is famous for its majesty and beauty.

D. Answer the following questions in one or two paragraphs

Question 1.
List the four major physical divisions of North America. Describe any one of them briefly.
Answer:
The four major physical divisions of North America are the Canadian or Laurentian shield, the Western Mountain System or Western Cordilleras, the eastern highlands or Appalachians Mountains and the central lowlands or Great Central Plains. The Central lowlands extend from Hindsom Bay in the north to
the Gulf of Mexico in the South covering distance of more than 6000 km and about 2000 km in width. They are also called the Great Central Plains. The plains are higher in West and slope northward in Canada. The main rivers which flow in these plains include Mackenzie, Mississippi—Missouri.

Question 2.
Why is the Canadian Shield region full of lakes ? Name any three lakes other than the five Great Lakes.
Answer:
The Canadian Shield is composed of oldest known hard rocks and the surface of land consists of many deep hollows of depression. When Ice Age ended, these depressions were filled by meltwater from glaciers and ice-sheets. Apart from the Great Lakes, Lake Winnipeg, Great Bear Lake, Great Slave Lake and Lake Athabasca are important lakes present in this region.

Question 3.
What are the various categories of lumberjacks ? What kind of work do they do ?
Answer:
The various categories of Lumberjacks include the high riggers, sawers or buckers. Skidders and haulers or transporters. The high riggers are people who climb the tall coniferous trees to cut off its branches first and then trunk.
The sawers use saw and axes to cut the trunk into lengths measuring 1 to 5 m.
The skidders mainly collect the logs and stack them along a frozen river bank, road or railway line.
The haulers ensure the transfer of logs down a river till they reach, a sawnill or factory. This include clearing ‘ log-jams’ with long poles or use sticks of dynamites to move logs which cause jams.

Question 4.
Describe how the lives and work of lumberjacks have changed in modern times.
Answer:
Lumberjacks used to have a very hard life in earlier days as their work of falling trees begins early followed by cutting off branches of fallen trees, skidding and hauling. They had to live in camps and start their days quiet early. But now settled communities of forest workers have developed. The forests are more accessible and they use power driven saws, powered cranes and automobiles.

E. Read books and encyclopaedias to find more information about Christopher Columbus, Amerigo Vespucci and other great explorers. Record your findings and stick some pictures alongside, if possible. Then share this information with other classmates and have a classroom discussion.
Answer:
Do it yourself.

F. Picture study

ICSE Solutions for Class 6 Geography Voyage Chapter 8 North America Location, Area, Political and Physical Features 1
This is a photograph of the Grand Canyon in Arizona.

Question 1.
Why do you think this canyon is called ‘Grand’ ?
Answer:
This Canyon is about 2000 m deep and 400 km long because it is world famous for its majesty and beauty, so it is called the Grand Canyon.

Question 2.
Name the river that has carved out the Grand Canyon.
Answer:
Its carved out of Colorado River.

ICSE Solutions for Class 7 Geography Voyage – Africa: Location, Area, Political & Physical Features

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ICSE Solutions for Class 7 Geography Voyage – Africa: Location, Area, Political & Physical Features

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 7 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 7 with Free PDF download option. Geography Voyage for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 7 Geography History & CivicsMathsPhysicsChemistryBiology

THINK AND ANSWER

Why did Africa remain unexplored for a long time ?
Answer:
The equator passes through the middle of the continent and most of Africa lies within the tropics. It is, therefore, the hottest continent.
People faced many difficulties while exploring Africa. In the north, the Sahara, the world’s largest desert, was impenetrable due to severe heat and dry conditions. Most of Africa consists of undulating plateaus, so it was difficult to reach the interior from the coastal areas. The rivers of Africa have many rapids and waterfalls, and are not fit for navigation. The extensive equatorial forests and swampy lands teeming with dangerous tsetse flies and poisonous insects discouraged explorers from entering the heart of the continent.

Discuss

Deforestation rate in Africa is twice the average for the rest of the world with more than four million hectares of primary forest disappearing every year. What could be the reasons for this.
Answer:
The reasons would be :

  1. Conversion of forests for subsistenance and commercial agriculture.
  2. Deforestation done because of commercial logging
  3. Other activities such as cattle rattling, cash crop plantations, and the construction of dams, roads and mines.

VALUES AND LIFE SKILLS

The Sahara Desert forms a large part of Africa. This desert extends from the Atlantic in the west to the Red Sea in the east.
Suppose you were going to the Sahara Desert. List the things you would take with you.
What kind of problems are you likely to face ?
How would you cope with them ?
Answer:
The things one should carry and the problems we can face are discussed below :
1. Preparing for Desert Emergencies —
(a) Wear clothing that minimizes sweat loss : Most of your body’s water loss happens through perspiration. Cover as much skin as possible with loose, light-weight clothing. This will trap the sweat against your skin, slowing evaporation and therefore water loss.
(b) Bring lots of extra water : Whenever you enter a desert, bring more water than you expect. While walking in sunshine and 40°C (104°F) heat, the average person loses 900 mL (30 oz) of sweat every hour. In an emergency situation, you’ll be thankful for any water you carried.

  1. Divide the water you’ re carrying among several containers. This minimizes the amount of water you can lose to one leak.
  2. Store the excess in a cool spot in your vehicle, away from direct sunlight.

(c) Bring food that packs the most nutrition in the least size and weight: Energy bars, pemmican, jerky, and trail mix are popular choices. Do your research, experiment beforehand, and be prepared. When wheeled vehicles break down, it’s just your two legs and the path to the next town, and you don’t want to be carrying anything nonessential.
(d) Pack survival equipment: Here are the bare essentials for a survival kit:

  1. Sturdy emergency blankets
  2. Cords or rope
  3. Water purification tablets
  4. First aid kit
  5. Fire starters
  6. Powerful flashlight or headlamp. LEDs last longest.
  7. Knife
  8. Compass
  9. Signal mirror
  10. Goggles and a dust mask or bandana (for dust storms)

2. Survival Tactics :
(a) Become nocturnal: In a desert survival situation, you do not want to be moving around during the day. The cooler night air enables you to travel farther and faster with minimum danger of heat exhaustion. In hot climates, this single decision will save your body about three liters (three quarts) of water per day.
(b) Stay in a shelter during the day: If you don’t have a shaded car to stay in, string cords between a pair of objects in a place that gets shade most of the day. Drape a sturdy emergency blanket over the cords. Place a few pieces of brush on top of the blanket, then cover it with another emergency blanket (this one can be a thin Mylar sheet). The gap of air between the two blankets insulates the shelter, keeping it cooler.
(c) Signal for help : Building a fire is a great way to make a signal, creating smoke during the day and light at night. While in transit, keep a signal mirror in reach to reflect light at passing aircraft or distant cars.
(d) Decide whether to stay in place : If you have a supply of water and someone knows where you are, staying in one place may be your best chance of rescue. Traveling to find help will exhaust you much faster than staying in place, and water loss will cut your survival time way down if you can’t find another supply. That said, if your water supplies are low, you will need to look for more. You cannot expect to survive more than a couple of days if you run out of water.
(e) Find water sources : If there’s been a rainstorm recently, you may find pockets of water in rock outcrops or flat stone surfaces. More often, you’ll need to search for areas with possible groundwater:

  1. Follow animal tracks leading downhill, birds circling around something, or even flying insects.
  2. Walk to the greenest vegetation you can see, especially large plants with wide leaves.

3. Recognizing Dangers
(a) Watch out for signs of dehydration : Many people make their journey much harder by underestimating their water needs. Trying to ration your supply is a mistake that can cost your life. If you notice any of the following symptoms, drink more water:

  1. Urine with a dark color or a noticeable smell.
  2. Dry skin
  3. Dizziness
  4. Fainting

(b) Rest if you experience heat exhaustion : If you feel lightheaded or nauseous, or if your skin feels cool and clammy, seek shade immediately. Rest and treat yourself as follows:

  1. Remove or loosen your clothing
  2. Sip a sports drink or slightly salty water (about 5 mL salt per liter water /1 tsp per quart).
  3. Apply wet cloth on your skin to aid cooling evaporation.

(c) Stay away from dangerous animals : Most mammals and reptiles will stay away from you, especially if they are alone. Follow the same practice and be aware of your surroundings to avoid accidentally cornering something.

EXERCISES

A. Choose the correct answer :

1. The strait that separates Europe from Africa is the

  1. Palk Srait
  2. Bering Strait
  3. Strait of Gibraltar
  4. trait of Magellan

2. A large portion of Africa lies in the

  1. desert
  2. tropics
  3. temperate region
  4. marshy land

3. The area in a desert where water can be found is called a/an

  1. pond
  2. well
  3. depression
  4. oasis

4. The Sudd is a

  1. lake
  2. swamp
  3. gulf
  4. cape

5. The largest lake in Africa is

  1. Lake Chad
  2. Lake Tana
  3. Lake Victoria
  4. Lake Tanganyika

B. Identify who I am

1. i am a country through which the Tropic of Capricorn passes: Namibia.
2. I am the southernmost tip of Africa: Cape of Good Hope.
3. I am a snow-capped mountain near the equator: Mt. Kilimanjaro.
4. I am the longest river of Africa: Nile.
5. I am a river that flows into Lake Chad: The Chari.
6. I am a lake that does not lie in the Great Rift Valley of Africa: Lake Victoria.
7. I am a river that flows through the Namib Desert: Okavango

C. Match the following:

ICSE Solutions for Class 7 Geography Voyage Chapter 14 Africa Location, Area, Political & Physical Features 1
Answer:

ICSE Solutions for Class 7 Geography Voyage Chapter 14 Africa Location, Area, Political & Physical Features 2

D. Give geographical reasons

Question 1.
People faced many difficulties while exploring Africa.
Answer:
It was difficult to explore Africa because of deserts like Sahara which have severe heat and dry conditions, the undulating plateaux, non-navigable rivers, extensive equatorial forests, swampy lands and poisonous insects.

Question 2.
The rivers of Africa are not very suitable for navigation in their lower course.
Answer:
The rivers have many rapids and waterfalls making them unfit for navigation.

Question 3.
The river Nile flows through a desert and yet has water throughout the year.
Answer:
River Nile has water throughout the year because its source is Lake Victoria which lies in the rainy equatorial region.

E. Answer the following questions briefly.

Question 1.
Give the latitudinal extent of Africa and explain why it is mostly a tropical continent.
Answer:
Latitudinal extent of Africa is 37°N to 35°S. Africa is known as mostly tropical continent because a large portion of Africa lies in the Tropics, the Tropic of cancer (23 1/2° N) in the North and the Tropic of Capricorn (23 1/2° S) in the South.

Question 2.
Name three great explorers connected with the African continent.
Answer:
David Livingstone, who discovered Victoria Falls in 1855. Mungo Park followed the course of the river Niger. Henry Morton Stanley traced the course of the river Congo from Lake Tanganyika to its mouth.

Question 3.
Name the major mountain ranges of Africa.
Answer:
The Atlas Mountains lie in north-western Africa. They are young fold mountains consisting of three parallel ranges—the Tell Atlas in the north, the High Atlas in the middle, and the Sahara Atlas in the south. The highest peak in the Atlas Mountains is Mt Toublkal, which remains snow-capped most of the year.

Question 4.
Name the lakes found in the Great Rift Valley.
Answer:
The lakes found in the Great Rift Valley are Lake Malawi, Lake Mobutu, Lake Edward and Lake Turkana.

Question 5.
How much time does it take the cocoa tree to yield cocoa pods ?
Answer:
An evergreen tropical plant, the cocoa tree grows to a height of 4 to 9 m. It begins to yield cocoa pods after about 5-7 years. Cocoa pods grow on the trunk and main branches. Each pod is about 18-25 cm long and contains pulp with beans.

F. Answer the following questions in one or two paragraphs

Question 1.
Elaborate on the achievements of the great explorers in opening up the continent of Africa.
Answer:
Explorers like David Livingstone discovered Victoria Falls. Mungo Park discovered the course of river Niger. Henry Morton Stanley traced the source of river Congo from Lake Tanganyika to its mouth.

Question 2.
Name the major physical divisions of Africa. Describe any one.
Answer:
Africa can be divided into the following physical divisions: the Atlas Mountains, the low central plateau, the high plateau of the south, the Great Rift Valley, the Nile and Congo-Zaire Basins, and the coastal plains.

  1. The Atlas Mountains lie in north-western Africa. They are young fold mountains.
  2. There are three parallel ranges – the Tell Atlas in the north, the High Atlas in the middle, and the Sahara Atlas in the south. The highest peak in the Atlas Mountains is Mt Toubkal, which remains snow-capped most of the year.
  3. The low central plateau extends from the Atlantic Coast in the west to the Nile Valley in the east. The Sahara Desert forms a part of this plateau. This desert extends from the Atlantic in the west to the Red Sea in the east, and covers an area of 8.6 million sq.km.
  4. The Great Rift Valley of Africa is a special physical feature of the southern plateau. It is a long narrow valley formed as a
    result of vertical cracks that developed because of the movements within the earth. It extends for a total distance of 5,000 km from Lake Malawi to the Red Sea and the Gulf of Aqaba to the Dead Sea in Jordan.

Question 3.
Describe the three important deserts found in Africa.
Answer:
The three important deserts are Sahara, The Namib, The Kalahari.
Sahara is part of the low Central Plateau. It is the largest desert in the world covering the area of 8.6 million square km.
The Namib, desert runs along the Western Coast in South-West Africa.
Kalahari desert lies in the Southern part of Africa forming part of High Plateau of South Africa.

Question 4.
What is a rift valley? How is it formed?
Answer:
The Great Rift Valley is a long narrow valley formed as a result of vertical cracks that developed because of movements within the earth. It extends for a total distance of5,000 km from Lake Malawi to Red Sea and the Gulf of Aqaba to Dead Sea in Jordan. Many freshwater lakes, such as Malawi, Tanganyika, and Turkana are found here.

Question 5.
Give an account of the major lakes of Africa.
Answer:
Lake Victoria is the largest lake of Africa. The river Chari flows into Lake Chad. Lake Tanganyika is one of the longest freshwater lake in the world. Other large lakes in Great Rift Valley are Malawi, Mobutu, Edward and Turkana.

G. Map work:
On a blank outline map of Africa, mark the following:

  1. The Cape of Good Hope
  2. The Drakensberg Mountains
  3. The Victoria Falls
  4. The Atlas Mountains
  5. The Nile River
  6. The Libyan Desert
  7. The Suez Canal

Answer:

ICSE Solutions for Class 7 Geography Voyage Chapter 14 Africa Location, Area, Political & Physical Features 3

H. Picture Study

ICSE Solutions for Class 7 Geography Voyage Chapter 14 Africa Location, Area, Political & Physical Features 4
This is a photograph of Victoria Falls.
Question 1.
Name the explorer who discovered it.
Answer:
David Livingstone discovered Victoria Falls in 1855.

Question 2.
On which river is this fall located ?
Answer:
Victoria Fall is located on Zambezi River.

LET’S DO SOMETHING

On a blank outline map of Africa

(a) Mark with brown lines the Atlas and the Drakensberg Mountains.
(b) Shade with yellow and label the Sahara Desert and the Kalahari Desert.
(c) Shade with light brown the plateau region of Africa, the Ethiopian and Adamawa Highlands.
(d) Colour with blue and label neatly all the surrounding water bodies, oceans, seas, bays, gulfs, and straits.

Answer:
Do it Yourself.

ICSE Solutions for Class 8 Geography Voyage – Asia: Climate and Natural Vegetation

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ICSE Solutions for Class 8 Geography Voyage – Asia: Climate and Natural Vegetation

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

ICSE Solutions Class 8 GeographyHistory & CivicsBiologyChemistryPhysicsMaths

Exercises

A. Fill in the blanks

  1. A few regions of South-west Asia receive winter rainfall from the temperate cyclones that originate over the Mediterranean Sea. (tropical cyclones, temperate cyclones, north-east winds, south-east winds)
  2. The Mediterranean climate is ideally suited growing citrus fruits, (equatorial, warm temperate east coast, Mediterranean, tropical monsoon).
  3. The tropical rain forests of Asia are dense and impenetrable, (steppes, mangrove forests, monsoon forests, tropical rain forests)
  4. About one-third of the land area of Asia is covered with forest.
  5.  Thermal electricity is produced by burning coal and petroleum.

B. Match the following

ICSE Solutions for Class 8 Geography Voyage Chapter 8 Asia Climate and Natural Vegetation 1
Answer:

ICSE Solutions for Class 8 Geography Voyage Chapter 8 Asia Climate and Natural Vegetation 2

C. Answer the following questions in brief

Question 1.
When does most of Asia receive maximum rainfall ? Give a reason for your answer.
Answer:
Most of the Asia receives maximum rainfall in the months of April, May and June. In summers, most of Asia has an average temperature of about 32°C. The hot air over the land rises and creates an area of low pressure. There is high pressure in the surrounding seas and oceans. So there is movement of warm moisture-laden onshore winds which are called monsoons. These winds cause heavy rainfall.

Question 2.
Name any two countries that experience Mediterranean climate.
Answer:
Syria, Turkey, Lebanon and Israel experience Mediterranean climate.

Question 3.
Explain how the climate of the cold temperate regions of Asia has affected the :

  1. Vegetation
  2. Wildlife

Answer:

  1. Vegetation of the cold temperate regions of Asia — These regions experience long severe winters with heavy snowfall and very short, cool summers with light rainfall. So the natural vegetation has adapted very well to the climate. The evergreen softwood trees of the region are conical in shape and have needle-like leaves. They are called coniferous trees as they have cones in which they bear their seeds. The common tree species are pine, fir, spruce, larch and cedar. The forests are also called as taiga.
  2. Wildlife — Several small to medium sized animals such as the fox, sable, bear, mink, lynx and squirrel are found here which have fur over their bodies to protect them from cold weather.

Question 4.
Name some wildlife species found in the taiga region, the tundra region, and the tropical deciduous forests of Asia..
Answer:
Wildlife species found in the taiga region are fox, sable, bear, mink, lynx and squirrel. Wildlife species found in the tundra region of Asia are polar bears, reindeer, foxes, seals and walruses.
Wildlife species found in the tropical deciduous forests of Asia are rhinoceros, elephants, bears, deer, apes, lions, tigers, leopards, etc.

Question 5.
Trees cannot grow of survive in the regions beyond the Arctic Circle in Asia. Why ?
Answer:
Trees or forests cannot grow or survive in the regions beyond the Arctic Circle in Asia because this region has long severe winters and the frozen subsoil which do not permit the growth of trees and this region is, therefore, devoid of forests.

D. Answer the following questions in one or two paragraphs

Question 1.
Identify the main factors that affect the climate of Asia. Explain any two of them.
Answer:
The Main factors that affect the climate of Asia are :

  1. Size and latitudinal extent — Asia is the largest continent with a large east-west extent. Also, it stretches across the torrid, temperate and frigid heat zones of the earth.
  2. Distance from the sea — Many parts of Asia are far away from the maritime influence of the seas and oceans and experience extreme conditions and continental climate. Places closer to the’Coasts enjoy equable or maritime climate.
  3. Relief features — like mountain ranges of Asia extend in the east-west direction and form barriers to the moisture laden winds and the cold winds.
  4. Wind — Moisture bearing winds from the south and cold winds of the north affect the climate of the places.
  5. Ocean Currents — The cold Oya Siwo and the warm Kuro Siwo ocean currents affect the temperatures of the coastal regions of Japan.

Question 2.
Describe the climatic conditions in Asia from October to March.
Answer:
From October to March, Asia experiences winter season as the northern hemisphere receives the slanting rays of the sun because of the tilt of the earth’s axis. The temperature falls to 0°C and even below freezing point in many parts of the northern Asia. The air over the land is cold and heavy and sinks causing high pressure. The surrounding oceans and seas ! have higher temperature and lower pressure so the cold air
moves from land (high pressure) to sea (low pressure). These winds are dry and hence most of the Asia receives no winter rainfall except South-East Asia, Japan, South-Eastern India i and parts of Sri Lanka, where the same winds cross the seas
and pick up moisture. A few regions of South-West Asia receive winter rainfall from the temperate cyclones that originate over the Mediterranean Sea.

Question 3.
Write about the Mediterranean climate experienced in Asia.
Answer:
The Mediterranean Climate in Asia is characterized by warm, dry summers and cool, wet winters.
Since these areas experience drought-like conditions in summer, the natural vegetation has adapted to the climate by developing long roots and spongy barks. The evergreen vegetation of oak, acacia, laurel, chestnut, walnut and olive trees is common. Orchards of citrus fruits such as lemons, and oranges, vineyards and farm grains have replaced the natural vegetation. In the absence of natural habitat, not much wildlife is found. Mostly domesticated animals such as donkeys, cattle and sheep are found.

Question 4.
Describe each of these forests :

  1. Tropical deciduous
  2. Equatorial rainforest.

Answer:

1. Tropical deciduous forests — They are found in tropical monsoon climate. These areas have hot wet summers with heavy rainfall and cool dry winters. Tropical deciduous forests are also called as monsoon forests. They have hardwood, broad-leaved trees which shed their leaves, in the dry season, usually in winter. Teak, Sal, shisham and mango are the common tree species. These thrive in regions of heavy rainfall. Grasses and thorny bushes grow in drier regions. Elephants, rhinoceros, bear, deer, apes, lion tiger, leopard, etc are some of the wildlife species found here.
Such forests are found in India, Pakistan, Bangladesh, Thailand, Myanmar, Vietnam, Laos, Cambodia and Southern China.

2. Equatorial rainforest — Such forests are found in equatorial climate where the temperatures are high of about 28-30°C and rainfall occurs all year round. Such climatic conditions have resulted in dense, hardwood forests with broad-leaved tree species such as mahogany, ebony, rosewood, cinchona, coconut and rubber. There are lianas, creepers and climbers, tall grass, ferns and bamboos that grow between the tall trees, which makes the forests dense and impenetrable. The forests are dark and gloomy as very little sunlight reaches the ground owing to the tall trees whose branches spread out, forming a canopy. Mostly arboreal or tree-dwelling animals such as monkey, apes and colourful birds are found. Reptiles such as lizards, snakes, crocodiles and insects are found in the swampy floors of the forests. Large animals such as elephants and wild cats are only found in the outskirts as the forest interior is too dense.
Such forests are found in countries located close to the equator like Malaysia, Indonesia, and Southern Philippines.

Question 5.
How has modernization changed the natural vegetation of the Mediterranean and steppe regions ?
Answer:

  • Mediterranean region — Due to modernization, most of the natural vegetation has been replaced by grain farms, orchards of citrus fruits such as lemons and oranges and vineyards.
  • Steppes region (Temperate Grassland) —Vast areas of grasslands have been converted into rich farmlands that grow wheat, barley and other food grains.

Question 6.
How are forests useful to the people of Asia?
Answer:
About one-third of the land area of Asia is covered with forest. Some of these forests provide hardwood, bamboo, sandalwood and camphor. They also provide other valuable forest products such as lac, resin, turpentine, honey, medicinal plants and herbs. Natural rubber is obtained from the latex of the rubber tree. The evergreen rainforest of the equatorial region and the monsoon forests of the tropical regions of Asia are the chief sources of these products.
Softwood forests yield softwood for making paper, pulp, newsprint, matchsticks and synthetic fibers such as rayon. These are obtained from trees such as birch, pine, cedar and fir, which grow in the taiga or coniferous forests region of northern Asia, especially Siberia.

Question 7.
Give an account of the mineral resources of Asia.
Answer:
Asia has vast deposits of different types of minerals such as iron ore (India, Malaysia, China, Russia, Japan, the Philippines, North Korea), coal (China, India, Kazakhstan, Russia), bauxite (India, Indonesia, Russia), and petroleum (Saudi Arabia, United Arab Emirates, Bahrain, Kuwait, Iran, Iraq, Malaysia, Indonesia, China, Russia).

E. Map study
On an outline map of Asia, mark the following:

  • area affected by the monsoons
  • regions of equatorial climate
  • regions of Mediterranean climate
  • areas under the steppes

Answer:
(a) Area affected by the monsoons

ICSE Solutions for Class 8 Geography Voyage Chapter 8 Asia Climate and Natural Vegetation 3
ICSE Solutions for Class 8 Geography Voyage Chapter 8 Asia Climate and Natural Vegetation 4

F. Picture study

Question 1.
Identify the animal seen in the photograph.
Answer:
Yak

Question 2.
In which climatic region of Asia can you find this animal ?
Answer:
Temperate or mid-latitude Desert region of Asia.

Extra Questions

Question 1.
Write a short note on summer conditions in Asia.
Answer:
From April to June, the sun rays fall directly over the northern hemisphere. In June, it shines overhead the Tropic of Cancer, so most of the continent of Asia, except the extreme northern parts beyond the Arctic Circle is warm with an average temperature of 32°C. Most of the Asia receives maximum rainfall in these months.

Question 2.
Why is Siberia so sparsely populated ?
Answer:
Siberia is sparsely populated as the climate here is very cold. Winters are long and severe with heavy snowfall which the summers are short and cool.

Question 3.
Write a short note on the tropical or hot desert climate and the natural vegetation and wildlife found there.
Answer:
Tropical or hot desert climate prevails in Arabia, Iran and the Thar desert in India and Pakistan. These regions experience very hot dry summers and very cold winters. The daily and annual ranges of temperature are very high and the areas receive less than 25 cm of rainfall annually.
As climatic conditions are harsh, vegetation is scarce and only thorny bushes, shrubs, cacti and clumps of dry grasses are found scattered in the region which is largely bare and devoid of vegetation. Date palms are found in the oases. Camels, horses, mules, gazelles, insects and lizards are some of the wildlife species found in the deserts.

Question 4.
What type of climate do China, Japan and Korea experience?
Answer:
China, Japan and Korea experiences warm temperate eastern margin or China type climate. It is similar to monsoon type except that the winters are colder. Snowfall occurs in winters while rainfall occurs in summer.

Question 5.
Which is the most common domesticated animal in Tibet ? What kind of climate is found in the Plateau of Tibet and the Gobi Desert ?
Answer:
Yak is the most common domesticated animal in Tibet. Temperate (or mid-latitude) desert climate is found in the Plateau of Tibet and the Gobi Desert. Very little rainfall, very cold winters with temperatures below the freezing point and very hot summers is found.

Question 6.
What increases the commercial value of forests in cool temperature eastern margin climate ?
Answer:
Oak, beech, maple and birch are the main trees and their occurrence in almost pure stands and predominance of only a handful of species greatly increase the commercial value of these forests.

Question 7.
List the major types of climate of Asia.
Answer:
The major types of climate of Asia are :

  1. Equatorial climate
  2. Tropical monsoon climate.
  3. Tropical or hot desert climate. .
  4. Warm temperate eastern margin or China type climate.
  5. Temperate or mid-latitude desert climate.
  6. Mediterranean climate
  7. Cool temperate eastern margin climate
  8. Temperate grassland or steppe climate
  9. Cold temperate or taiga climate
  10. Arctic or tundra climate.

Question 8.
What are the different types of vegetation found in varied climatic conditions of Asia ?
Answer:
The different types of vegetation in Asian climate include dense evergreen hardwood forests, tropical deciduous forest, thorny bushes, coarse short grasses, evergreen softwood trees and mosses and lichens.

9. Fill in the blanks.

  1. The areas away from the coasts experience continental (extreme), climate while places closer to the coasts experience maritime (equable) climate.
  2. World’s highest surface temperature of 71°C has been recorded in Dasht-eLut in Iran.
  3. Mawsynram in Meghalaya receives the heaviest rainfall in the world.
  4. Verkhoyansk in Russia is the coldest region in Asia with an average temperature of-51 °C. ’
  5. Most of the Asia receives no rainfall in winter.
  6. Convectional rainfall occurs almost daily around 4 o’ clock in equatorial climate region of Asia.
  7. Latex is the milky sap of rubber tree which is collected and used to make rubber for commercial purposes.
  8. The equatorial (tropical) rainforests are different from the rainforests of the Amazon and Zaire basins because of their nearness to the sea.
  9. India has tropical monsoon climate and tropical deciduous (monsoon) forests.
  10. Date palms are found in the Oases in hot deserts.
  11. The Gobi Desert stretches across large parts of Mongolia and China.
  12. Yak is one of the most commonly domesticated animals in the temperature desert regions of Asia.
  13. The two-humped Bactrian camel is a well-known animal of temperate grassland or steppe.
  14. The temperate grassland region of Central Asia is called steppe.
  15. The forests of the cold temperate regions, have coniferous trees with needle like leaves.
  16. The coniferous forests in cold temperate climate are called as Taiga.
  17. The treeless plains in the Arctic climate are called Tundra.

Map Skills
On a physical map of Asia, show the different types of climate and natural vegetation
Answer:

ICSE Solutions for Class 8 Geography Voyage Chapter 8 Asia Climate and Natural Vegetation 5

ICSE Solutions for Class 6 History and Civics – Rise of Kingdoms and Republics

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ICSE Solutions for Class 6 History and Civics – Rise of Kingdoms and Republics

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 6 History and Civics Chapter 7 Rise of Kingdoms and Republics. You can download the History and Civics ICSE Solutions for Class 6 with Free PDF download option. History and Civics for Class 6 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 6 History & Civics Geography Biology Chemistry Physics Maths

Exercise

I. Fill in the blanks:

  1. More powerful territories in the 6th century were referred to as Mahajanapadas.
  2. In monarchy kingship was hereditary.
  3. Magadha emerged as the most powerful kingdom in North India in the sixth century BC.
  4. Alexander the Great invaded India in 326 BC.
  5. Porus impressed Alexander by his bravery and wisdom.
  6. A new school of art called Gandhara developed, as a result of Alexander’s invasion of India.

II. Match Column A with Column B:
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 1
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 2
Answer:
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 3

III. Long Answer type Questions:

Question 1.
What were the main advantages that helped Magadha to emerge as the most powerful kingdom?
Answer:
With the help of following advantages Magadha emerged as the most powerful kingdom

  1. The presence of natural resources helped Magadha’s rise to power in the 6th century BC.
  2. Rich deposits of iron ore contributed to the making of effective iron weapons and agricultural tools.
  3. Due to strategic locations of both the capitals, Rajgriha (Rajgir) and Pataliputra, it was difficult for any rival to capture these cities.
  4. The Magadhan rulers had well-organised, efficient and powerful almies, which consisted of elephants, horses and chariots.
  5. The Magadhan territory being fertile, produced surplus food.
  6. The Magadhan rulers gained immensely from trade and commerce.
  7. The rivers like Ganga, Son, etc. provided waterways.

Question 2.
What policy did Bimbisara follow to extend his territories?
Answer:
Bimbisara extended his territories through conquests and marriages. He married the daughter of the king of Kosala and received the province of Kashi as dowry. The ruler of Kosala
thus became his friend. He also married the Lichchavi princess of Vaishali and thereby extended his friendship ties in this region. His third wife was the daughter of a chieftain of Punjab. Infact, Bimbisara was the first Indian king who brought a large part of Northern India under a unified political control.

IV. Short Answer type Questions:

  1. What is meant by the term Janapada ?
    Ans. The meaning of word ‘Janapada’ is the place where people put their pad or feet. The Janapada consisted of many villages and towns.
  2. Name the three most important Mahajanapadas.
    Ans. Kosala, Magadha, Avanti.
  3. Name the king who conquered Anga ?
    Ans. Bimbisara conquered Anga.
  4. Name the Magadhan king who killed his father ?
    Ans. Ajatashatru killed his father Bimbisara.
  5. Name a few towns that grew up in early days.
    Ans. Kasbi, Rajgriha, Vaishali, etc.
  6. Name the territories conquered by Bimbisara and Ajatashatru.
    Ans. Anga, Kosala, Vaishali, etc.

V. Give reasons why

  1. Bimbisara married princesses of his neighboring kingdoms.
    Ans. Bimbisara married princesses of his neighboring kingdoms to extend his territory.
  2. Deposits of iron in Magadha helped it become a powerful kingdom.
    Ans. Rich deposits of iron ore in Magadha contributed to the making of effective iron weapons and agricultural tools.

Textbook Keywords

  1. Janapadas: They were large states that grew in India as a result of wars and conquests. The word means the place where people place their feet.
  2. Mahajanapadas:  They were the powerful Janapadas. There were sixteen Mahajanapadas.
  3. Shakyas and Lichchhavis: They were the name of democratic republics ruled by representatives elected by the people.
  4. Gandhara School of Art: An Indo-Greek school of art that grew in India as a result of cultural contact with the Greeks.

Additional Questions

A. Fill in blanks.

  1. The pastoral Aryan tribes of the Early Vedic Period roamed about in search of new pastures. In the Later Vedic Period they began to cultivate the land.
  2. Large kingdoms were known as Janapadas and the more powerful among these were known as mahajanapadas.
  3. The four powerful kingdom in the Later Vedic Period were Vatsa, Avanti, Kosala and Magadha.
  4. The first important king of Magadha was Bimbisara.
  5. Alexander invaded India during the reign of the Magadha
  6. Dhana Nanda was overthrown by Chandragupta Maurya.
  7. Ambhi the ruler of Taxila, offered to help Alexander to defeat Porus.
  8. Alexander’s invasion led to the establishments of four different trade routes by land and sea.
  9. India’s cultural contact with the Greeks led to the development of a style of art known as the Gandhara School of Art.
  10. The power of the small states in north-western India was shattered by Alexander’s invasion.

B. Match the following.

ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 4
Answer:
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 5
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 6

C. Answer the following questions.

Question 1.
State the reasons for the emergence of the mahajanapadas.
Answer:
Surplus production, increased prosperity and the desire to expand further are the reasons for emergence of the mahajanapadas.

Question 2.
How many mahajanapadas are mentioned in the religious texts of the 6th century BCE?
Answer:
There are sixteen manhajanpadas are mentioned in the religious texts of the 6th century BCE.

Question 3.
How did the conquest of Anga benefit Magadha?
Answer:
The conquest of Anga brought the river port of Champa under his control of Magadha. The rich deposits of iron or found in this region contributed to the development of a strong and stable economy for Magadha.

Question 4.
Why was Alexander unable to conquer Magadha?
Answer:
Alexander was unable to Conquer Magadha because his army refused to advance any further. The army was war-weary and homesick and was not willing to face the powerful army of Magadha.

Question 5.
Mention briefly the effects of Alexander’s invasion.
Answer:
The effects of Alexander’s invasion were following.

  1. His invasion led to the establishment of four different trade routes by land and sea.
  2. Alexander’s historians have left dated records of his campaigns.
  3. The cultural contact with the Greeks led to the growth of the Indo-Greek School of Art known as Grandhara school of Art.

D. State whether the following are true of false.

  1. Magadha belonged to the Iron Age.
    False
  2. Alexander was the king of Rome.
    False
  3. The capital city of Magadha was Pataliputra.
    True
  4. Mahapadma Nanda was the last king of the Nanda dynasty.
    False
  5. Ambhi and Porus were allies.
    False

F. Picture study.
This is a painting of two important kings who became friends after war.
ICSE Solutions for Class 6 History and Civics - Rise of Kingdoms and Republics 7

Question 1.
Can you identify the two rulers in this painting ?
Answer:
Alexander and Porus are the two rulers in the painting.

Question 2.
Give an account of the earlier developments that led to this event.
Answer:
Porus was the ruler of the area lying between the rivers Jhelum and Chenab. Ambhi offered to help Alexander to defeat Porus. Porus fought heroically but was defeated. Fie was captured and brought before Alexandar who asked him how he would like to be treated. Porus replied ‘As one king should treat another king’ Alexandar was so impressed with reply that he set Pours free and they became friends.

Question 3.
Name the most powerful kingdom in India during this time. Which dynasty ruled this kingdom?
Answer:
Magadha was the most powerful kingdom in India during this time. Nanda dynasty ruled this kingdom.

Question 4.
Who overthrew the last ruler of this dynasty ? Name the empire established by him.
Answer:
Chandragupta Maurya overthrew the last ruler of Nanda dynasty. He established Maurya Empire.

ICSE Solutions for Class 7 History and Civics – Jahangir, Shah Jahan and Aurangzeb

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ICSE Solutions for Class 7 History and Civics – Jahangir, Shah Jahan and Aurangzeb

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 7 History and Civics. You can download the History and Civics ICSE Solutions for Class 7 with Free PDF download option. History and Civics for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 7 History & CivicsGeographyMathsPhysicsChemistryBiology

Important Words

  • The chain of justice is said to be a chain installed by Jahangir. It was made of pure gold with 60 bells attached to it, between the palace and the banks of the river Yamuna. Anyone could ring the bell and seek justice.
  • Engineer King is the name by which Shah Jahan is known, as his patronage of architecture is one of the most important characteristics of his reign.
  • Shahjahanabad was a new capital city build by Shah Jahan. Now, it is known as Old Delhi.

Time To Learn

I. Fill in the blanks:

  1. Taj Mahal, a symbol of love, shows a variety of cultural influences.
  2. Jahangir installed a chain of justice for the seekers of justice.
  3. The treaty of Purandhar was signed between Mughals and Rajput ruler Jain Singh.
  4. The original name of Nur Jahan was Mehrunnisa.
  5. Bijapur was annexed in AD 1686.
  6. Aurangzeb reimposed Jazia and pilgrimage tax.
  7. Guru Tegh Bahadur, ninth Sikh guru, was executed on Aurangzeb’s order.
  8. The Sikhs were organised into a military force called the Khalsa.

II. Match Column A with Columb B:
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 1
Answer:
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 2
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 3

III. State whether the following statements are True or False:

  1. Jahangir left the administration in the hands of his queen,Nur Jahan.
    True.
  2.  Nur Jahan’s influence was good and lasting for theMughal Empire.
    False.
  3. Shah Jahan had to fight for the throne.
    True.
  4. Shah Jahan married Mumtaz Mahal, in whose memory the built the Taj.
    True.
  5. Shah Jahan died in AD 1666, as a captive in the fort of Agra.
     True.
  6. Aurangzeb had friendly relation with the Rajputs and theMarathas.
     False.
  7. The Sikhs were hostile to the Mughal Emperor after the execution of the ninth Sikh guru.
    True.
  8. Aurangzeb died in 1707 in the Red Fort at Delhi.
    False.
  9. Aurangzeb reimposed .
    True.

IV. Answer the following questions briefly:

Question 1.
Jahangir is sometimes called a mixture of opposites. Discuss.
Answer:
Sometimes Jahangir was needlessly cruel and inflicted punishments disproportionate to the offence committed. For this combination of good qualities and bad qualities of his character some historian have rightly called him as ‘the mixture of opposites’.

Question 2.
How did Jahangir deal with the European traders? Name two travellers who visited Jahangir’s court.
Answer:
Jahangir was on good terms with the Portuguese traders. He gave them some trade concessions.Captain Hawkins and Sir Thomas Roe, visited Jahangir’s court.

Question 3.
The age of Shah Jahan is the Golden Age of Mughal rule. Do you agree? Give reasons for your answer.
Answer:
Yes, The age of Shah Jahan is the Golden Age of Mughal rule. The points describing are as follows:

  1. During the regin of Shah Jahan, there was undisturbed peace within the country. There were no foreign threats and Shah Jahan too devoted most of his time in maintaining peace and order in the country. Trade and commerce flourished bringing in lots of wealth. The land was fertile and revenue flowed into the treasury.
  2. Shah Jahan carried out many works of public welfare. Roads, canals, bridges, sarais, etc., were constructed for the welfare of the people. Similarly, during the famine and plague he did a lot to relieve the people of their sufferings.
  3. Shah Jahan had a natural love for magnificence, which was reflected in the buildings that he constructed. His reign is, in fact, called the Golden Age of the Mughal Architecture. One of the most important buildings constructed by him is the Taj Mahal, which was built in the memory of his beloved wife Mumtaz Mahal.

Question 4.
Describe the religious policy of Aurangzeb. What were its results?
Answer:
Aurangzeb’s religious policy had two aspects i.e:

  1. To promote the tenets of Islam and to ensure that the people led their lives accordingly.
  2. To adopt anti-Hindu measures.

The religious fanaticism of Aurangzeb overshadowed his virtues. His reversal of Akbar’s policy of religious toleration resulted in weakening the entire structure of the Mughal empire. It led to several conflicts and wars in different parts of the country.
These conflicts were:

  1. Conflict with the Jats
  2. Conflict with the Satnamos
  3. Conflict with the Sikhs
  4. Conflicts with the Rajput’s
  5. Conflict with the Marathas.

All these rebellions destroyed the peace of the empire, disrupted its economy, weakened the administrative structure, diminished its military strength, led to the failure of Aurangzeb to make any impact. Ultimately all these contributed to the downfall of the Mughal enterprise.

Question 5.
Who were the Sikhs? How did they emerge as a political power?
Answer:
Khalsa’s were the sikhs.
Open wars started between the Sikhs and the Mughals after Ninth Sikh Guru, Guru Tegh Bahadur was executed on Aurangzeb’s order. Aurangzeb and his successors had to face continous trouble from the sikhs. After Aurangzeb’s death, his successors failed to check the rising power of the Sikhs. The Sikhs gradually emerged as a political power.

Question 6.
Briefly describe aurangzeb’s clash with : (a) the Rajputs, (b) the Marathas, (c) the Sikhs.
Answer:
(a)
The Rajputs were not well treated by Aurangzeb. Raja Jai Singh and Raja Jaswant Singh were kept away from the court at Delhi. Raja Jai Singh was a loyal general but he was suspected and insulted after the escape of Shivaji.
(b)
Conflicts started between the Mughals and the Marathas over the conquest over the conquest of Bijapur.
(c)
The relations between the Sikhs and the Muslims were already strained because of Guru Arjan Dev’s execution at the hands of Jahangir for helping his rebel son. From then onwards, the Sikhs had become the enemies of the Mughals. Guru Gobind Singh, the tenth Guru and son of Guru Tegh Bahadur, continued the policy of his father. He organised the Open wars started between the Sikhs and the Mughals.

Question 7.
Why do you think Aurangzeb reimposed some taxes?
Answer:
Aurangzeb reimposed Jazia and pilgrimage tax because of his othodox relious policies.

Question 8.
Explain the factors responsible for the decline of the Mughal empire.
Answer:
The factors responsible for the decline of the Mughal empire are:

  1. Aurangzeb’s Faulty Policies: Aurangzeb followed an orthodox religious policy. He reimposed Jazia and pilgrimage tax. Thus, he antagonised not only the Hindus but also the Muslims. He also made enemies of communities like the Jats, Sikhs and the Marathas.
  2. Aurangzeb’s Deccan Policy: The conquests of Bijapur and Golconda made the empire too big to be administered efficiently. Moreover, Aurangzeb’s long stay in the Deccan (almost 25 years) neglected the administration of his empire in the North. His absence also helped the rise of the Maratha power.
  3. Weak Successors: Aurangzeb’s successors were incompetent and weak, and they could not suppress the revolts or control the nobles. They become too ambitious, and independent. Eventually, the governors of the Deccan, Awadh and Bengal declared themselves as independent rulers.
  4. Empty Treasury: Aurangzeb maintained a large standing army. But his long wars in the Deccan caused a big drain on the state treasury. Thus, after the death of Aurangzeb (AD 1707), the treasury became empty and the later Mughal rulers were unable to pay the soldiers and officers and meet their expenses.

V. Write a short note on 

Question 1.
Aurangzeb’s Deccan Campaigns
Answer:
Aurangzeb wanted to crush the growing powers of the Maratha’s. As these people were very strong and courageous and they also did not accept the over lordship of the ruler. This empire was also very vast and prosperous, so Aurangzeb wanted to have it under his control.

Question 2.
Abdali’s invasion on India
Answer:
Ahmad Shah Abdali invaded India several times between 1747 and 1767. He gave a crushing defeat to the Marathas in 1761 in the third Battle of Panipat. The Marathas could not regain their past power ever again.

Additional Questions
(Jahangir, Shah Jahan and Aurangzeb)

A. Fill in the blanks:

  1. Nur Jahan became the virtual ruler of the Mughal empire.
  2. During the final years of Jahangir’s reign, there was a power struggle between Nur Jahan and Shah Jahan.
  3. Shah Jahan’s reign is often referred to as the Golden Age of the Mughal empire.
  4. Aurangzeb spent the first half of his reign in the North and the second half in the Deccan.
  5. Aurangzeb spent the last twenty six years of his reign fighting against the Marathas and the Sultanates of Bijapur and Golconda.

B. Match the following:
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 4
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 5
Answer:
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 6

 

C. Choose the correct answer:

1. The foundations laid by Akbar/Babur/Humayun were so strong that Jahangir did not have any major problems maintaining the empire.
Ans. The foundations laid by Akbar were so strong that Jahangir did not have any major problems maintaining the empire.

2. Shah Jahan built the magnificent Agra Fort/Taj Mahal/ Red Fort in the memory of his wife Mumtaz Mahal.
Ans. Shah Jahan built the magnificent Taj Mahal in the memory of his wife Mumtaz Mahal.

3. Shah Jahan built a new city called Fatehpur Sikri/ Daulatabad/Shahjahanabad.
Ans. Shah Jahan built a new city called Shahjahanabad.

4. Aurangzeb’s reign can be roughly divided into four/ three/two
Ans. Aurangzeb’s reign can be roughly divided into two periods.

5. One of the most serious challenges faced by Aurangzeb came from the Sikhs/Marathas/Rajputs in the Deccan.
Ans. One of the most serious challenges faced by Aurangzeb came from the Marathas in the Deccan.

D. State whether the following are true or false:

  1. Jahangir defeated the Rana of Mewar.
     True.                                                                              ’
  2. Jahangir is said to have installed a chain of justice.
    True.
  3. The Peacock Throne was taken to Persia by Nadir Shah.
    True.
  4. The Jama Masjid is said to be the most perfect of Jahangir’s buildings.
    False. Correct: The Jama Masjid is said to be the most perfect of Shah Jahan’s buildings.

E. Answer the following questions in one or two words/ sentences:

1. Why did Jahangir not face any major problems in maintaining his large empire?
Ans. The foundations laid by Akbar were so strong that Jahangir did not have any major problems maintaining the empire.

2. Name Jahangir’s son who rebelled against him.
Ans. The rebellion of his eldest son, Khusrau.

3.Why is Shah Jahan known as the Engineer King?
Ans.Shah Jahan is known as Engineer King due to his work in the field of architecture. During his time magnificent buildings were constructed which are remembered still now. Some of the finest examples of monuments during his reign are — the magnificent Taj Mahal at Agra, the Moti Masjid at Agra Fort and the dignified Jama Masjid at Delhi.

4. Which fort did Shah Jahan build in the new city of Shahjahanabad?
Ans.Red Fort.

5. Who succeeded Shah Jahan as the Mughal emperor?
Ans.Shah Jahan’s third son, Aurangzeb.

6. State any one major cause of the decline of the Mughal empire.
Ans.He spent too much money on military expeditions and building magnificent monuments which drained the royal treasury.

7. What was the nature of Aurangzeb’s Rajput policy in the early years of his reign?
Ans.During the early years of his reign, Aurangzeb followed Akbar’s policy of friendship with the Rajputs. He granted the Rajput rulers high mansabs and tried to win their support.

8. What were the objectives of Aurangzeb’s Deccan policy?
Ans.Aurangzeb wanted to crush the growing powers of the Maratha’s. As these people were veiy strong and courageous and they also did not accept the overlordship of the ruler. This empire was also very vast and prosperous, so Aurangzeb wanted to have it under his control.

9. Why did the annexation of Bijapur and Golconda prove harmful for the Mughal empire?
Ans.It became too vast and unwieldy and brought the Mughals into direct contact with the Marathas.

F. Answer the following questions briefly:

Question 1.
Jahangir fulfilled Akbar’s unrealized imperial dreams by conquering Mewar. Explain.
Answer:
Jahangir sent an expedition against Rana Amar Singh of Mewar who, like his father, Rana Pratap Singh, had refused to acknowledge the overlordship of the Mughal emperor. The Rana of Mewar was defeated. He pledged his loyalty to Jahangir, who treated him with courtesy. He allowed the Rana to retain his territory and appointed his son, Kama, as a military commander in the imperial army. The submission of Mewar established the paramountcy of Mughal authority in Rajputana and marked the fall of the last bastion of Rajput resistance.

Question 2.
To what extent were Jahangir’s Deccan campaigns successful?
Answer:
Jahangir sent an expedition under Prince Khurram who managed to recapture the fort of Ahmadnagar. Prince Khurram was honoured with the title of Shah Jahan (Lord of the World). The war continued and by the end of Jahangir’s reign, Ahmadnagar reasserted its independence and remained outside Mughal control.

Question 3.
What qualities did Nur Jahan possess to make her worthy of her name?
Answer:
Nur Jahan means-light of the world and according to her name she possessed all the qualities like she was intelligent, beautiful, educated and cultured. She was a good poet and designer too. She designed new varieties of fabrics and jewellery. She was also strong and courageous and helped Jahangir to take decisions in matters related to the government.

Question 4.
Nur Jahan was very ambitious and eventually became the power behind the throne. Explain.|
Answer:
Nur Jahan was ambitious and soon became the power behind the throne. Jahangir consulted her on all matters concerning the affairs of the government. Nur Jahan soon became the virtual ruler of the Mughal empire. Graudally, Jahangir left the administration in her hands and spent his time indulging in his addiction to wine and opium. Coins began to be issued jointly in the name of Jahangir and Nur Jahan. Nur Jahan used her positioin and influence to appoint her father, brother and other relatives to important posts in the administration. Her niece, Mumtaz Mahal, was married to Jahangir’s third son, Khurram (Shah Jahan).

Question 5.
Shah Jahan’s reign was an age of splendour and cultural brilliance. In this context, discuss:
(a) Taj Mahal
(b) Red Fort
Answer:
(a) Taj Mahal: It took more than 20 years to complete the Taj Mahal, at a cost of one crore rupees at that time. It is made of pure white marble and is lavishly decorated with semi-precious stones and lace-like screens. It is an octagonal monument with a splendid dome and four slender minerals, set in a beautiful garden,
(b) Red Fort: This building is made of red sandstone. There are many splendid buildings inside the Red Fort. The Diwan-i-Khas is the most impressive. Its ceiling is made of silver. Its walls are made of marble and decorated with gold and semi-precious stones.

Question 6.
Why did Aurangzeb’s Deccan campaign against the Marathas prove to be a ruinous misadventure? What were the long-term consequences of this campaign?
Answer:
The Deccan campaign proved to be a ruinous misadventure that showed lack of political wisdom.
Suspicious by nature, he did not trust his sons and nobles. His officials were like puppets on strings. Aurangzeb’s supervision of every department often bordered on interference. His policy of discrimination between his subjects on grounds of faith also made him unpopular. He was a man of unshakeable convictions and tried very hard to reach his goals by doing what he thought was right. As he lay on his deathbed, he wrote several letters to his son. In one letter he wrote, ‘I know not who I am or why I came into the world … I have not done well for the country or its people . . . I know what punishment will be in store for me to suffer.’ During the first half of the 19th century ce, the great Mughal empire decayed and disintegrated. The Mughal emperors lost their power and glory and their vast empire finally shrank to a few square miles around Delhi.

Question 7.
Why did Aurangzeb fail as a ruler?
Answer:
Aurangzeb possessed qualities of an ideal man but he was failure as a ruler. Like his father he was not able to follow the policy of religious tolerance and friendship. His list of enemies not only included Rajput’s but also Sikhs and the Marathas. He was also very suspicious by nature, which was not liked by his officials. His policy of discrimination with his subjects also made him an unpopular ruler.

Question 8.
Briefly explain the negative aspects of Shah Jahan’s reign that eventually led to the decline of the Mughal empire.
Answer:
The policy of religious tolerance and friendship with the Rajputs was continued by Shah Jahan.Behind the glamour and the glitter of Shah Jahan’s reign, however, lurked some disturbing shadows.

  1. Shah Jahan’s military expeditions to Central Asia and Kandahar and the extravagant building projects drained the royal treasury.
  2. To improve the country’s financial resources, heavier taxes were imposed on the peasantry.
  3.  According to Bernier, the French traveller, many villages were mined and left desolate. This setback to agriculture became a major cause of the decline of the Mughal empire.
  4.  The failure of military campaigns during this period was an indication of the decline of the military might of the Mughals.
  5. The administrative machinery had grown in size but corruption had crept in.

G Picture study:

This is a picture of a 17th century-CE monument, built in red sandstone by a Mughal emperor.
ICSE Solutions for Class 7 History and Civics - Jahangir, Shah Jahan and Aurangzeb 7

Question 1.
Identify the monument.
Answer:
Red Fort.

Question 2.
Where is it located?
Answer:
Old Delhi.

Question 3.
Who built this monuments?
Answer:
ShahJahan.

Question 4.
Name two important buildings inside this monument.
Answer:
(a) Diwan-i-Khas
(b) Diwan-i-Aam

Question 5.
Mention its important features.
Answer:
Important features are as:
The Diwan-i-Khas is the most impressive. Its ceiling is made of silver and its walls are made of marble decorated with gold and semi-precious stones.
Diwan-i-Aam was Shah Jahan’s Peacock Throne. It had a canopy supported by twelve emerald pillars, each bearing two peacocks studded with gems. This golden throne, which took 7 years to complete, was taken to Persia by Nadir Shah in 1739 ce.

Selina Concise Biology Class 6 ICSE Solutions – Digestive System

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Selina Concise Biology Class 6 ICSE Solutions – Digestive System

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for Selina Concise ICSE Solutions for Class 6 Biology. You can download the Selina Concise Biology ICSE Solutions for Class 6 with Free PDF download option. Selina Publishers Concise Biology for Class 6 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

Selina Class 6 Biology ICSE SolutionsChemistryPhysicsMathsGeographyHistory & Civics

Selina Concise ICSE Solutions for Class 6 Biology Chapter 4 Digestive System

Synopsis:

  • The food we consume fall into seven different catagories.
    1. carbohydrates
    2. fats
    3. proteins
    4. minerals
    5. vitamins
    6. water
    7. roughage
  • The process of nutrition is conducted in five steps
    1. ingestion
    2. digestion
    3. absorption
    4. assimilation
    5. egestion
  • When some part of food is chewed, the tongue makes it a spherical mass called Bolus.
  • Peristalsis is a wave of constriction in the circular muscles in the wall of the gut to push the food further into the food canal.
  • The food canal is also called alimentary canal which starts from the mouth and ends at the anus.
  • The digestive glands include
    1. Salivary glands
    2. Liver
    3. Pancreas
  • The teeth which are similar in size and shape are called homodont teeth.
    They are usually found in fishes, frogs, reptiles etc.
  • The last molar on each side in each j aw is called wisdom tooth which appears at the age of 17-20 years.
  • The human teeth develop in two sets; the first set is called milk teeth or temporary teeth while the second set which replaces the milk teeth are called permament teeth.
  • The milk teeth are twenty in number while the permament are thirty two in number.
  • The part of the teeth which can be seen is called crown while the part which is fixed in the jaw is called root.
  • The tooth is made up of:
    1. enamel
    2. dentin
    3. pulp
  • The hardest substance of the body is called Enamel.
  • The yellow, stick substance found on the teeth due to poor oral hygeine is called plaque. It consists of sugar and bacteria.
  • Mineralised or hard plaque is called tartar.
  • The functions of tongue are:
    1. manipulates food while chewing
    2. helps in tasting the food
    3. mixes food with saliva
    4. cleans the teeth.
    5. helps in speaking.
  • The enzyme contained in saliva is called amylase which digests starch into glucose.
  • The food pipe is the oesophagus. No digestion takes here
    Selina Concise Biology Class 6 ICSE Solutions - Digestive System 1
    Selina Concise Biology Class 6 ICSE Solutions - Digestive System 2
  • The organ which serves for both digestion and absorption of the food is small intestine.
  • The small intestine is 7 metres long while the large intestine is 1.5 metres long.
  • No enzyme is secreted by the large intestine.
  • Glucose, amino acids, vitamins and minerals are transported to the liver.
  • Amino acids are used in the production of proteins for growth and repair of tissues.

Review Questions

Multiple Choice Questions :

1. Put a tick (✓) against the most appropriate alternative in the following statements.

(1) The teeth which help in tearing the food are the:
(a) Incisors
(b) Canines
(c) Premolars
(d) Molars

(ii) Last molar tooth in human beings is called:
(a) Adult tooth
(b) Wisdom tooth
(c) Child tooth
(d) Elders tooth

(iii) The hardest substance in your body?
(a) Dentine
(b) Bone
(c) Cement
(d) Enamel

(iv) Saliva converts starch into:
(a) Glucose
(b) Sucrose
(c) Maltose
(d) Lactose

(v) Proteins of the milk are converted into curd by the enzyme:
(a) Trypsin
(b) Rennin
(c) Pepsin
(d) Steapsin

(vi) Bile juice ¡s produced by :
(a) Stomach
(b) Liver
(e) Pancreas
(d) Gall bladder

1. Write True or False in the following statements.

  1. Molars help in cutting and tearing food.
    False
    Correct — Molars help in finer crushing and grinding.
  2. Carbohydrates are digested into glucose.
    True
  3. Proteins are digested into fatty acids.
    False 
    Correct — Proteins is digested into amino acids.

2. Fill in the blanks.

  1. The teeth called are a total of four in number on the sides of incisors.
  2. The teeth called canines are a total of four in number on the sides of incisors.
  3. Pharynx is a common opening of food pipe and wind pipe.
  4. Molars are meant for crushing the food.
  5. Incisors are used for biting and cutting the food.
  6. The canines are used for tearing the food.
  7.  The premolars and molars are used for crushing and grinding the food.
  8.  In an adult human, there are a total of 32 teeth.
  9. The human teeth appear in two sets, the first set is called primary which consists of only twenty teeth.

3. Name the following :

  1. End product of starch after digestion — glucose.
  2. The organ where protein digestion-begins — stomach.
  3. The organ into which the pancreatic juice and the bile juice are poured — small intestine.
  4. The enzyme which digests fat — lipases.
  5. The simplest form of carbohydrates — glucose. ‘
  6. The part of alimentary canal where water from undigested food is absorbed — large intestine.
  7. The end-product of proteins after digestion — amino acids.

4. Identify and name the four type of teeth shown below and give their functions.
Answer :
Selina Concise Biology Class 6 ICSE Solutions - Digestive System 3
A — incisor
Function -Its major function is biting and cutting of food.
B — canine
Function — Its major function is tearing of the food.
C — pre-molar
Function — Used for crushing and grinding of food.
D — molar
Function — Used for crushing and grinding of food.

5. State whether the following statements are True or False.

(i) Wisdom tooth appears at the age of 5-6 years when the child starts going to school.
(ii) The temporary set of teeth includes incisors, canines and premolars only.
(iii) The ducts from the salivary glands open into the duodenum.
(iv) Saliva changes starch into maltose.
Answer :
(iv) True (V) Saliva changes starch into maltose.

6.Fill in the blanks in the table (1-5) by selecting the suitable names of substances from the list given below:
(steapsin, peptones, fatty acids, proteoses, protein).
Selina Concise Biology Class 6 ICSE Solutions - Digestive System 4
Answer :
Selina Concise Biology Class 6 ICSE Solutions - Digestive System 5

Question 7.
(i) Name the juice secreted by the liver.
Ans. Bile
(ii) Name the organ where this juice is temporarily stored.
Ans. Gallbladder
(iii) What is the main function of this juice ?
Ans. The main function of bile is digestion of fats.

Question 8.
Name the three enzymes found in pancreatic juice.
(i)….. (ii)….. (iii) ……
Answer :
(i) Starch digesting — amylase
(ii) Protein digesting — trypsin
(iii) Fat – digesting — lipases

Question 9.
Name the three regions of the large intestine.
Answer :

  1. Caecum
  2. Colon
  3. Rectum

Question 10.
Given alongside is the diagram of the human alimentary canal.
(i) Name the parts 1-11 indicated by guidelines.
1. … 2. … 3. … 4. … 5. … 6. …
7. … 8. … 9. … 10. … 11 ….
(ii) State the function of the juice secreted by the part 1.
(iii) State the function of the three enzymes found in the juice secreted by part 3.
Selina Concise Biology Class 6 ICSE Solutions - Digestive System 6
Answer :
(i) 1 Stomach
2—Bile duct
3 — Pancreas
4 — Large intestine
5 — Small intestine
6 — Rectum
7—Appendix
8 — Pancreatic duct
9— Gall Bladder
10—Liver
11—Anus
(ii) The gastric juice being acidic kills the germs and activates pepsin.
(iii)

  1. amylase — digests starch
  2. trypsin — digests protein
  3. lipase — digests fat

Long Answer Questions
Question 1.
Define the term nutrition.
Answer :
The process by which living beings receive the food and utilise it to grow and become healthy is called nutrition.
On the basis of nutrition, living beings can be classified into the following types:

  1. Holozoites
  2. Parasites
  3. Saprophytes
  4. Symbionts

Holozoits can be further classified into

  1. herbivores
  2. carnivores
  3. ommivores

Question 2.
What is the role of the liver and the pancreas respectively in the digestion of food ?
Answer :

  1. Liver: It produces a green yellow fluid called the bile which emulsify fats making it easy to be digested. The bile also contains sodium bicarbonate which neutralises the acid of food coming from the stomach and makes it alkaline.
  2. Pancreas: It produces the digestive juice called the pancreatic juice which acts on carbohydrates, proteins and fats and convert them into simpler units called glucose, amino acids and fatty acdis respectively.

Question 3.
Name the digestive juice secreted by the stomach and give its function.
Answer :
The digestive juice secreted by the stomach is the gastric juice.
The gastric juice contains

  1. — water
  2. — hydrochloric acid
  3. — enzyme

Which have the following roles :

  1. Hydrochloric acid serves to kill the germs and activates pepsin.
    Pepsin converts proteins into peptones and proteoses.
  2. Enzyme rennin converts the milk caesin into curd.

Answer the following questions:
Question 4(i).
(i) Name the types of teeth seen in humans.
Answer :
Human teeth are of four kinds:

  1. Incisors are the four front teeth at the middle of each jaw. They are chisel-shaped for biting and cutting.
  2. Canines are one on either side of the incisors in each jaw. They are pointed for tearing the food.
  3. Premolars are two on each side of canines in each jaw. They help in crushing and grinding the food.
  4. Molars are the last three teeth on each side in each jaw. They have broad uneven surface for finer crushing and grinding of ingested food.

Question 4 (ii).
How is the small intestine best suited for the digestion and absorption of food ?
Answer :
The small intestine’s inner lining contain a large number of tiny finger-like projections called villi. The villi greatly increases the inner surface area for the absorption of digested food.

Question 4(iii).
What do you mean by absorption of food ?
Answer :
The absorption of food means to pass the digested food products into the blood system and lymph vessels to be used further by body for various life functions.

Question 5.
Define the following terms
Egestion, digestion, assimilation.
Answer :
Egestion — The process of removal of the undigested food from the body is defined as egestion.
Digestion — The process of breaking the food into smaller and simpler substances so that they can be easily used by the body is called digestion.
Assimilation — The process of using the digested food by the body is called assimilation.

Question 6.
Rewrite the following parts of the human alimentary canal in their correct sequence
Stomach, Oesophagus, Large instestine, Small intestine, Pharynx.
Answer :
Pharynx — Oesophagus → Stomach → Small-
intestine → Large intestine.

Question 7.
What is the fate of excess glucose in our body ?
Answer :
The excess glucose is converted by the liver into insoluble glycogen and stores it, whenever required. Liver can reconvert the glycogen into glucose.

Question 8.
Define the term ‘digestion’.
Answer :
The process of converting the complex food substances into simpler and smaller units so that they can be easily utilised by the body is defined as digestion.
e.g. proteins are converted to amino acids.

Question 9.
State the four ways in which saliva is useful to us.
Answer :
The four ways in which saliva is useful to us are:

  1. Moistens and lubricates the oral cavity and the tongue to make speaking and swallowing easy.
  2. Acts as a solvent, dissolving some part of food to stimulate taste
  3. Cleans the mouth and destroys germs
  4. Initiates digestion by converting starch into simpler form, maltose.

Question 10.
Food are classified into three groups on the basis of the function they perform in our body. Name the three categories, and briefly give their functions. Also give their two sources each.
Answer :
Function

  1. energy giving food
  2. bodybuilding food
  3. regulatory and protective foods

Nutrient

  1. carbohydrates and fats
  2. proteins
  3. vitamins and minerals

Food

  1. cereals, fats, sugar
  2. pulses, milk, meat chicken
  3. fruits and vegetables

Selina Concise Biology Class 7 ICSE Solutions – Photosynthesis and Respiration

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Selina Concise Biology Class 7 ICSE Solutions – Photosynthesis and Respiration

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for Selina Concise ICSE Solutions for Class 7 Biology. You can download the Selina Concise Biology ICSE Solutions for Class 7 with Free PDF download option. Selina Publishers Concise Biology for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

Selina Class 7 Biology ICSE SolutionsChemistryPhysicsMathsGeographyHistory & Civics

Selina Concise ICSE Solutions for Class 7 Biology Chapter 4 Photosynthesis and Respiration

Synopsis —

  • The process of preparing or synthesising food using water from the soil and carbon dioxide from the air, together chlorophyll and sunlight is called photosynthesis.
  • Photosynthesis occurs in the mesophyll cells of the leaf. These cells contain numerous plastids called chloroplasts.
  • With in the plastids is present the green pigment called chlorophyll.
  • On the lower surface of the leaf are numerous pores called stomata, which open into small air cavities inside the leaf.
  • Stomata are tiny openings found mainly on the lower surface of leaves. These openings are surrounded by a pair of bean¬shaped cells called guard cells.
  • All plants have a transport system called vascular system. It is composed of two types of tissues called xylem and phloem.
  • There are two end-products of photosynthesis :
    • Glucose (C6H12O6)
    • Oxygen
  • The energy released during respiration is stored as chemical energy in the form of ATP — adenosine tri-phosphate.
  • Aerobic respiration —
    C6 H12O6+6O2  →  6CO2+6H2O+38ATP
    Anaerobic respiration —
    C6H12O6 →  2C2H5OH+2CO2+2ATP
  • During vigorous exercise, the cells respire anaerobically and form lactic acid which accumulate in the muscle cells causing fatigue and pain.
  • Cellular respiration is called internal respiration which takes place in the cells of living organisms.
    Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 1
  • The frog respires through
    1. skinmouth
    2. lining
    3. lungs.
  • The respiratory organs of the fish are gills.
  • Transpiration is the loss of water in the form of water vapour from the aerial parts of the plant.
  • Transpiration occurs through stomata.
  • The factors which affect the rate of transpiration are 
    1. Sunlight
    2. Temperature
    3. Wind
    4. Humidity
  • The significance of transpiration
    •  Maintain the concentration of the sap inside the plant body.
    • Causes cooling effect

Review Questions

Multiple Choice Questions
1. Put a tick (✓ ) against the most appropriate alternative in the following statements.
(i) Carbohydrates are stored by plants in the form of:
(a) Vitamins
(b) Proteins
(c) Fats
(d) Glucose 

(ii) Stomata are present on the surface of:
(a) Leaves
(b) Roots
(c) Stem
(d) Flower petals

(iii) Which one of the following is an end-product of photosynthesis ?
(a) Fructose
(b) Glucose
(c) Cellulose
(d) Lactose

Short Answer Questions

1. Why do leaves generally look green ?
Answer:
The green colour of a leaf is due to the presence of chlorophyll.

2. Which four of the following are needed for photosyn-thesis in a leaf:
(i) Carbon dioxide:
(ii) Oxygen:
(iii) Nitrates :
(iv) Water:
(v) Chlorophyll:
(vi) Soil:
(vii) Light:
Answer:
(i) Carbon dioxide: from air
(iv) Water: from soil
(v) Chlorophyll: contained in leaf
(vii) Light: from sunlight

3. What is the source of energy for photosynthesis ?
Answer:
Light is the ultimate source of energy in photosynthesis because plants take in the sunlight CO2 and H2O and converts it into glucose.

4. Which gas is taken in and which one is given out by the leaf in bright sunlight ?
(i) Taken in :
(ii) Given out:
Answer:
(i) Carbon dioxide
(ii) Oxygen

5. Suppose we compare the leaf with a factory, match the items in Column A with those in Column B.
ColumnA Column B
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 2

Answer:
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 3

6. State whether the following statements are True or False:

(i) Green plants prepare their food by using two raw materials, oxygen and water.
False. Green plants prepare their food by using raw materials, CO, chlorophyll and water.
(ii) The chlorophyll enables the plants to use light energy.
 True
(iii) The free oxygen in the atmospheric air is the result of photosynthesis.
 True
(iv) Photosynthesis occurs only in chlorophyll-containing parts of the plant.
True

7. Differentiate between aerobic and anaerobic respiration. Write the overall chemical equations of the two kinds of respiration in plants.
(i) Aerobic:
(ii) Anaerobic:
Answer:
Aerobic respiration

  1. It occurs in the presence of oxygen.
  2. Here there is complete breakdown of glucose releasing carbon-di-oxide, energy. water and energy.
  3. More energy is released (38 ATP).

Anaerobic respiration

  1. It occurs in the absence of oxygen.
  2. There is partial breakdown of glucose into ethyl alohol, carbon-di-oxide and
  3. Lesser energy is released (2 ATP).

(i) Aerobic respiration:
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 4
(ii) Anaerobic respiration:
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 5
Question 8.
 Explain how photosynthesis is different from respiration.
Answer:
Photosynthesis

  1. Anabolic process
  2. Food is produced here.
  3. Oxygen is by-product.
  4. Chlorophyll and sunlight are required.
  5. Occur only during daytime.
  6. Occurs in green plants only.

Respiration

  1. Catabolic process
  2. Food is broken down form here to release energy
  3. Carbon-di-oxide is the by-product.
  4. Chlorophyll and sunlight are notrequired.
  5. Occurs all the time
  6. Occurs in all living beings including plants.

Photosynthesis :
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 6

Respiration:

C6H12O6+6O→6CO2+6H20+energy

Question 9.
 Do the plants respire all day and night or only during the night ?
Answer:
The plants respire only during the night. Plants take in oxygen and give out carbon dioxide. Hence, there is some truth in the belief that one should not sleep under the trees at night.

Question 10.
 What happens to the energy liberated during respiration?
Answer:
The energy liberated during respiration is utilised for carrying out various life processes.
Some of the energy liberated during the breakdown of 03 the glucose molecule, is in the form of heat, but a large part of it is converted into chemical energy called Adenosine Triphosphate (ATP). Any activity inside the cell is carried out by the energy released by these ATP molecules.

Long Answer Questions

Question 1.
In order to carry out photosynthesis, what are the substances that a plant must take in ? Also mention their sources.
Answer:
For preparing food, the plants require the following :

  1. Water (from soil)
  2. Carbon dioxide (from air)
  3. Chlorophyll (contained in the leaf)
  4. Energy (from sunlight)

The process of preparing or synthesising food using water from the soil and carbon dioxide from the air, together chlorophyll and sunlight is called photosynthesis. This entire process is a series of complex chemical reactions Photosynthesis is represented as follows:
Selina Concise Biology Class 7 ICSE Solutions - Photosynthesis and Respiration 7

Question 2. 
What is the role of chlorophyll in photosynthesis ?
Answer:
This pigment is of utmost importance as it absorbs the sunlight which provides energy for the process of photosynthesis occurs inside the chloroplast of the leaf.

Question 3.
Do plants need oxygen ? If so, what is its source ?
Answer:
Yes plants need oxygen, all the free oxygen in the atmospheric air is the result of photosynthesis. No animal can survive without oxygen as it is needed for respiration. Even the plants use the same oxygen in dark for their own respiration.

ICSE Solutions for Class 7 Geography Voyage – Greenhouse Effect and Global Warming

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ICSE Solutions for Class 7 Geography Voyage – Greenhouse Effect and Global Warming

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 7 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 7 with Free PDF download option. Geography Voyage for Class 7 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 7 Geography History & CivicsMathsPhysicsChemistryBiology

DISCUSS

Collect rainfall data from the website of Indian Meteorological Department (IMD) for Mumbai, Chennai, Delhi and Kolkata and discuss how rainfall patterns have changed in the last 5 years.
Answer:
ICSE Solutions for Class 7 Geography Voyage Chapter 4 Greenhouse Effect and Global Warming 1
Mumbai receives maximum rainfall in 2016 and minimum rainfall in 2012.
Chennai receives maximum rainfall in 2013 and minimum rainfall in 2012.
Delhi receives maximum rainfall in 2013 and minimum rainfall in 2014.
Kolkata receives maximum rainfall in 2013 and minimum rainfall in 2014.

VALUES AND LIFE SKILLS :

We need to understand that global warming, climate change, acid rain and ozone depletion are all happening because of our dependence on fossil fuels and CFC-based technologies. Therefore, the need of the hour is to reduce
our dependence on them.
What can you do in this regard ?
Answer:
The ways to reduce our dependency on them are :

  1. By using materials such as bamboo, recycled metal and organic paints in construction of buildings.
  2. By using solar energy to heat and light homes and offices.
  3. By using clean fuel like CNG and unleaded petrol to run vehicles.
  4. By making changes in everyday practices such as
    (a) choosing to travel in public vehicles, biking, walking or using a car pool.
    (b) buying energy efficient household appliances.
    (c) replacing light bulbs with CFL bulbs.

EXERCISES

A. Fill in the blanks.

1. Carbon dioxide and methane, nitrous oxide, water vapour and CFCs are examples of greenhouse gases.
2. Global Warming is a major cause of climate change.
3. The increase in earth’s temperature is called global warming.
4. The layer of atmosphere where ozone is found is called stratosphere.
5. The ozone layer protects us from the ultraviolet rays of the sun.

B. Write True or False.

1. Aeroplanes flying in the sky cause global warming.
Answer. True.

2. Forest fires do not cause global warming.
Answer. False.
Correct : Forest fires do cause global warming.

3. Ozone is found in the troposphere.
Answer. False.
Correct : Ozone is found in the stratosphere.

4. The ozone layer is harmful for humans and animals.
Answer. False.
Correct : The ozone layer is not harmful for humans and animals.

5. CFCs and BFCs protect the ozone layer.
Answer. False.
Correct : CFCs and BFCs deplete the ozone layer.

C. Choose the correct option.

Question 1.
Oxygen/Carbon dioxide is a greenhouse gas.
Answer:
Carbon dioxide is a greenhouse gas.

Question 2.
Use of fossil fuels/hydroelectricity causes global warming.
Answer:
Use of fossil fuels causes global warming.

Question 3.
Cattle release methane / CFCs.
Answer:
Cattle release methane.

Question 4.
Global warming will reduce/increase climate change.
Answer:
Global warming will increase climate change.

Question 5.
The ozone layer is found between 20 and 40/40 and 60 km above the earth’s surface.
Answer:
The ozone layer is found between 20 and 40 and above the earth’s surface.

D. Match the following

ICSE Solutions for Class 7 Geography Voyage Chapter 4 Greenhouse Effect and Global Warming 2
Answer:
ICSE Solutions for Class 7 Geography Voyage Chapter 4 Greenhouse Effect and Global Warming 3

E. Answer the following questions in brief 

Question 1.
Why do we call carbon dioxide a greenhouse gas?
Answer:
Carbon dioxide is called greenhouse gas because it absorbs
Infrared radiations. A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range.

Question 2.
Name two more greenhouse gases.
Answer:
Methane and water vapour are other greenhouse gases.

Question 3.
How will countries like Bangladesh and Thailand be affected by global warming?
Answer:
Climate change will cause melting of polar ice caps with huge chunks of icebergs several kilometres across breaking off from the mainland. This is already taking place around the Arctic and in Antarctica. The result will be an increase in the volume of ocean waters. Countries like Bangladesh, Thailand and Malaysia and the Southeastern parts of USA like the States of Florida and Louisiana would be swamped by flood water along its shores.

Question 4.
What is responsible for causing a hole in the ozone layer?
Answer:
The release of large amount of CFCs or chlorofluorocarbons and BFCs or bromofluorocarbons by industries are responsible for the formation of holes in the ozone layer.

Question 5.
Name some diseases that are caused due to exposure to ultraviolet rays of the sun.
Answer:
Exposure to UV rays can cause sunburn, cataract, hair loss, skin cancer and birth deformities.

F. Answer the following questions in one or two paragraphs 

Question 1.
How is the greenhouse effect created?
Answer:
The ‘greenhouse effect’ takes place when the ‘sun’s rays heat the earth. This heat is absorbed by the surface of the earth and some of it is radiated back into the atmosphere. However, a part of this heat is trapped in the atmosphere by gases such as water vapour, carbon dioxide and methane while the rest escapes into space. These gases let in light from the sun but prevent the heat from escaping like the glass walls of a greenhouse. They also act like a mirror and reflect back to the earth some of the trapped heat energy. The more greenhouse gases (GHGs) are present in the atmosphere, the more heat is trapped, subsequently making the earth warmer.

Question 2.
State three causes that have led to an increase in greenhouse gases in the atmosphere.
Answer:
The causes that have led to the increase in greenhouse gases (GHGs) are:

  1. Increase in industries
  2. Increase in deforestation
  3. Increase in atmospheric pollution due to emissions from chimneys of factories
  4. Increase in natural disasters like floods, volcanic eruptions and earthquakes that release large amounts of smoke, dust and gases into the atmosphere
  5. Increase in the methane content of the atmosphere because of large-scale cattle rearing, since cattle release methane
  6. Expansion of cies and towns

Question 3.
What do you understand by the term ‘global warming’?
Answer:
The greenhouse gases in the atmosphere trap a part of the heat radiated back by the earth, increasing its temperature. The increase in the earth’s temperature is called global warming.

Question 4.
State some anthropogenic (man-made) causes of global warming.
Answer:
Man-made causes of global warming ‘include burning of fossil fuels, cutting of forests, using refrigerators, air conditioners, aerosols, factories belching smoke, increase in methane content of the atmosphere because of large-scale cattle rearing, expansion of cities and towns.

Question 5.
Global warming does not augur well for our planet earth. State at least three reasons to support this statement.
Answer:
Global warming is not good for our planet as

(a) It will worsen climate changes leading to food shortages.
(b) Many forms of wildlife are now’ at risk and since climate change and deforestation are causing disappearance of their habitat.
(c) Climate change will cause melting of polar caps resulting in the increase in the volume of ocean waters.

G. Picture study.
ICSE Solutions for Class 7 Geography Voyage Chapter 4 Greenhouse Effect and Global Warming 4

Question 1.
Which region of the world is seen in the picture?
Answer:
Antarctica and Arctic Poles.

Question 2.
How is it going to be affected by global warming?
Answer:
Global warming causes melting of polar ice-caps with huge chunks of icebergs several kilometres across breaking off from the mainland resulting in increase in volume of ocean waters. The increase in the volume of ocean waters will result in rising of sea levels. Countries like Bangladesh, Thailand and Malaysia and the Southeastern parts of USA like the States of Florida and Louisiana would be swamped by flood water along their shores.

LETS DO SOMETHING

Question 1.
Imagine that you are an active member of the Greenpeace. Write a two-page appeal addressed to the Prime Minister of India stating why you think that increasing number of vehicles on roads will be disastrous to the nation in the long run.
Answer:
August 25, 2017,
Mr. Narendra Modi,
Prime Minister of India
Dear Prime Minister Modi,

It is with great optimism and hope that we are following news about the meeting you will have with U.S. President Trump, at this critical time in our planet’s future. 2017 is the year for making decisive commitments towards tackling climate change together. As the elected leader of the world’s largest democracy, and a country with much to lose from run away climate change, the hopes of 1.3 billion Indian citizens rest on you. Along with them, and the millions of people worldwide who will inevitably be affected by decisions made this year, we hope you will successfully push the United States, and the developed world, towards an ambitious and equitable global agreement to rein in climate change.

We congratulate you on setting new and ambitious renewable energy targets, and urge a focus on decentralized renewable energy as the fastest, most cost-effective way to tackle India’s energy poverty challenge. At the same time, we believe that continued growth in coal power is not in the interests of common Indians as it imposes a significantly higher cost on people’s health, livelihood of communities and the environment, and will prove far more expensive than renewable energy. We hope you will secure much-needed support from global partners, civil society and investors – including the United States administration – to realize these renewable energy goals.

Being the member of the Greenpeace, I would like to bring in your kind notice that I found that the number of vehicles has increased considerably in India in the past five years, which is one of the sources of pollution. In the recently released World Health Organization (WHO) report on pollution, the situation of the city is not so encouraging in terms of pollution in the air.
Due to increase in number of vehicles over the years, the city roads witness frequent traffic congestions, but above all, the vehicles emitting pollutants are affecting environment badly. The recently-released WHO report shows that India has 2.5 microns of diameter (PM2.5) concentration of 68 micrograms particulate matter per meter cube. However, the WHO guideline values for particulate matter is 10 microgram per meter cube for PM2.5.

“The air pollution consists of many pollutants, among other particulate matter. These particles are able to penetrate deeply into the respiratory tract and therefore constitute a risk for health by increasing mortality from respiratory infections and diseases, lung cancer, and selected cardiovascular diseases,” says the WHO report.

New patients with respiratory problems are constantly being reported in hospitals. Recently, the many big cities are witnessing a flow of traffic on city roads consisting high end cars too. Moreover, as far as public transport is concerned, the government-owned low floor buses could be seen plying on the road emitting black smoke causing problems for pedestrians, bikers and other roadside vendors. Mr. Avinash Chowdhry senior member of Greenpeace took out a rally of school children at Statue

Circle (Mumbai) on the eve of World Environment Day said, “Men’s health is determined by his environment. He is greatest enemy of his own health. Environmental pollution is one of the reasons of cardiovascular diseases, hypertension and diabetes.”
Collaboration between the government and civil society is essential to secure a bright future for India and the planet. Greenpeace looks forward to working with the Indian government on our common objective of ensuring clean, affordable renewable energy for all.

Sincerely,
VeenuGopal,
Interim Executive Director, Greenpeace

Question 2.
Make a collage using pictures or a chart to show the various causes and consequences of global warming.
Answer:
You can take idea from the picture given below and can make a collage of your own.
ICSE Solutions for Class 7 Geography Voyage Chapter 4 Greenhouse Effect and Global Warming 5

Selina Concise Physics Class 6 ICSE Solutions – Simple Machines

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Selina Concise Physics Class 6 ICSE Solutions – Simple Machines

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for Selina Concise ICSE Solutions for Class 6 Physics. You can download the Selina Concise Physics ICSE Solutions for Class 6 with Free PDF download option. Selina Publishers Concise Physics for Class 6 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

Selina Class 6 Physics ICSE SolutionsChemistryBiologyMathsGeographyHistory & Civics

Selina Concise ICSE Solutions for Class 6 Physics Chapter 4 Simple Machines

  • Synposis
  • Work is said to be done when a force applied on a body moves it. If the body does not move on applying a force on it, no work is done by the force.
  • The capacity of doing work is called energy.
  • A machine is a device which helps us to do work more easily.
  • A machine enables us to apply a less effort for a load greater than the effort or to apply the effort at convenient point and in a desired direction.
  • Some machines are simple and some are complex.
  • The mechanical advantage of a machine is the ratio of the load to the effort, i.e., Mechanical advantage = Load / Effort
  • Smaller the effort required for a certain load, greater is the mechanical advantage of the machine.
  • The efficiency of a machine is the ratio of the useful work done on the load by the machine to the work put into the machine by the effort, i.e.
    Efficiency = Work output / Work input
  • The efficiency of an ideal machine is 1 (or 100 per cent).
  • The efficiency of an actual machine is less than 1 because some part of the work put into the machine is lost in overcoming the friction between the moving parts of the machine.
  • A lever is a simple machine which we most commonly use in our daily life. It is a rod which can turn about a fixed point called the fulcrum.
  • The mechanical advantage of a lever is equal to the ratio of the effort arm to the load arm, i.e. Mechanical advantage of a lever = Effort arm / Load arm
    The levers are of three kinds :
    Class I levers which have fulcrum in between the load and the effort.
    Class II levers which have load in between fulcrum and the effort.
    Class III levers which have effort in between the fulcrum and the load.
  • The mechanical advantage of class I lever can be 1, more than 1 or less than 1.
  • The mechanical advantage of class II levers is always more than 1.
  • The mechanical advantage of class III levers is always less than 1.
  • A pulley is a simple machine which is used for raising a load up by applying the effort downwards.
  • The mechanical advantage of an ideal pulley is 1. In an actual pulley, due to friction, the mechanical advantage is less than 1 (i.e., the effort is more than the load).
  • The pulley allow us to apply the effort downwards which is a convenient direction.
  • The wheel and axle is a simple machine having a wheel and an axle. The linear motion of axle is obtained by rotating the wheel so as to reduce friction. Example: Steering wheel, screw drivers, water tap etc.
  • An inclined plane is a simple machine which is used to move a load up with a less effort. It is a sloping (or slanting) surface.
  • Less the slope of the inclined plane, less is the effort needed to push a load up.
  • The mechanical advantage of an inclined plane is greater than 1 (i. e. a less effort is required to push a heavy load up an inclined plane).
  • A wedge is a sharp edge formed by joining the two inclined planes together. Example: nail, knife, axe, plough etc.
  • A screw is a modified form of an inclined plane.
  • A screwjack is a simple machine having a combination of a screw and a lever. It is used to lift the heavy vehicles such as cars, trucks, buses etc.
  • Machines are used for our convenience. Therefore, we should take proper care of a machine by painting the machine parts to avoid rusting, lubricating its parts to reduce friction etc. This increases the life span of the machine.

Test yourself

A. Objective Questions

1. State whether the following statements are True or False.

(a) A boy does work while pushing a wall.
Answer. False

(b) A machine performs work by itself.
Answer. False

(c) In an ideal machine, work done on load is equal to the work done by effort.
Answer. True

(d) All levers are force multipliers.
Answer. False

(e) A pulley changes the direction of force.
Answer. True

(f) An inclined plane always has the mechanical advantage more than 1.
Answer. True

2. Fill in the blanks

(a) The useful work done by an actual machine is always less than the work done on the machine.
(b) In class II levers, the load is in between fulcrum and effort.
(c) The mechanical advantage of class III lever is always less than 1.
(d) A pulley is used to change the direction of effort.
(e) Mechanical advantage of an inclined plane is always greater than 1.

3. Match the following

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 1

Answer.

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 2
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 3

4. Select the correct alternatives

(a) For an ideal machine, the efficiency is

  1. greater than unity
  2. less than unity
  3. equal to unity
  4. depends on the value of load

(b) Mechanical advantage of a machine is defined as:

  1. Load X Effort
  2. Load / Effort
  3. Load + Effort
  4. Effort / Load

(c) The mechanical advantage of a lever is equal to:

  1. Load arm / Effort arm
  2. Effort arm / Load arm
  3. Load arm + Effort arm
  4. Load arn — Effort arm

(d) A pulley is used because it

  1. has the mechanical advantage greater than one
  2. has 100% efficiency
  3. helps to apply the force in a convenient direction
  4. requires more effort to raise a less load.

(e) Wheel is used with axle because

  1. sliding friction is less than the rolling friction
  2. rolling friction is less than the sliding friction
  3. they work as the inclined plane
  4. They help us to change the direction of force.

B. Short/Long Answer Questions

Question 1.
When is work said to be done by a force ?
Answer:
Work is said to be done when a force moves an obj ect through a distance in its own direction.

Question 2.
What is energy ?
Answer:
Energy: The ability or capacity to do work is called energy.

Question 3.
What do you understand by a machine ?
Answer:
Machine: A machine is a device that allows us to do work with less effort. Machines make our work easier to do. Machines have made our li ves comfortable and faster.

Question 4.
What is the principle on which a machine works ?
Answer:
Principle of a Machine: The work output of a machine is equal to the work input.

Question 5.
State two functions of a machine.
Answer:
Various functions that a machine can perform are:

  1. Changing the direction of applied force — Example: When a flag is hoisted with the help of a pulley.
  2. Changing the magnitude of applied force — Example: Bottle opener multiplies the applied force and much less effort is required to open the cap.
  3. Applying force at a convenient point — Example: In a pair of scissors, the input force is applied at the handle of the scissors which cuts the paper at the other end of the blade.
  4. Changing the speed of an object — Example: While riding a bicycle, force is applied on pedals which multiplies the speed.

Question 6.
Name six simple machines. Give an example of each machine.
Answer:
The Simple Machines and there examples are as follows:

  1. The lever: Examples are a crow bar, claw hammer, a pair of pilers etc.
  2. The Inclined plane: Examples are ramp, staircase, hilly roads etc.
  3. The wedge: Examples are knife, axe, plough, nail etc.
  4. Screw: Examples are A screw.
  5. The wheel and axle: Examples are steering wheel of a car, bicycle pedal etc.
  6. The pulley: Examples are a pulley used in raising a load.

Question 7.
Define the term ‘work input’ and ‘work output’ in relation to a machine.
Answer:
Work input is work done on a machine equal to the effort force times the distance through which the force is applied.
Work output is work that is done by a machine equals resistance force times the distance through which the force applied.
For an ideal machine, the work output is equal to the work input i. e. the efficiency.

Question 8.
Explain the term mechanical advantage of a machine.
Answer:
The mechanical advantage of a machine is the ratio of the load to the effort. In other words
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 4

Question 9.
Define the term efficiency of a machine.
Answer:
The ratio of the work done by the machine to the work done on the machine is called efficiency of a machine
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 5
(Work done by a machine is called the output energy and the work done on a machine is called the input energy.)

Question 10.
What is an ideal machine ?
Answer:
A machine is which no part of the work done on the machine is wasted, is called an ideal or perfect machine. Thus, for an ideal machine, the work output is equal to the work input, i.e., the efficiency of an ideal machine is 1 (or 100 per cent).

Question 11.
Can a machine have an efficiency of 100% ? Give a reason to support your answer.
Answer:
Efficiency of a machine is always less than 100% as output energy is always less than the input energy, because some energy is lost to overcome friction.

Question 12.
A machine is 75% efficient’. What do you understand by this statement ?
Answer:
If a machine is 75% efficient, it means that 75% of the work input to the machine is obtained as the useful work output. The remaining 25% of the work input has been lost in overcoming the friction.

Question 13.
What is a lever ?
Answer:
Lever: A lever is a simple rigid bar which is free to move around a point called fulcrum.

Question 14.
Describe three orders of levers giving an example of each. Draw neat diagrams showing the positions of fulcrum, load and effort in each kind of lever.
Answer:
The levers are of three kinds :
Class I levers which have fulcrum in between the load and the effort.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 6
Class II levers which have load in between the fulcrum and the effort.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 7
Class III levers which has effort in between the fulcrum and the Load
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 8

Question 15.
What do you mean by the mechanical advantage of a lever ?
Answer:
The mechanical advantage of a lever is equal to the ratio of the effort arm to the load arm. This is also called the principle of a lever.

Question 16.
Which class of lever has the mechanical advantage always more than 1 ? Give an example.
Answer:
The mechanical advantage of class II levers is always more- than 1.
Example – Nut cracker, wheel barrow, bottle opener etc.

Question 17.
Which class of lever has the mechanical advantage always less than 1 ? Give an example.
Answer:
The mechanical advantage of class III levers is always less than 1.
Example: a pair of tongs, sugar tongs, knife, forceps etc.

Question 18.
Give one example of class I lever in each case where the mechanical advantage is

  1. more than 1
  2. equal to 1
  3. less than 1.

Answer:

  1. more than 1: Load arm of pliers
  2. equal to 1: See – saw
  3. less than 1: The load arm of a pair of scissors.

Question 19.
Name the class to which the following levers belong:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 9
Answer:
(a) A pair of scissors — Class I lever
(b) a lemon squeezer — Class II lever
(c) a nut cracker — Class II lever
(d) a pair of sugar tongs — Class III lever
(e) a beam balance — Class I lever
(f) an oar rowing a boat — Class I lever
(g) a wheel barrow — Class II lever
(h) a see saw — Class I lever
(i) a pair of pilers — Class I lever
(j) a crow bar — Class I lever

Question 20.
The diagram given below shows the three kinds of levers. Name the class of each lever and give one example of each class.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 10
Answer:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 11
Examples : The examples of class I levers are : a see saw, a pair of scissors, a pair of pilers, crow bar, common balance, spoon opening the lid of a tin can, handle of a hand pump.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 12
Examples : The examples of lever of class II are : nut cracker, wheel barrow, paper cutter, mango, lemon squeezer, bottle opener.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 13
Examples: The examples of levers of class III are : a pair of tongs, sugar tongs, knife, forceps,-forearm of a person holding a load, spade for lifting soil or coal.

Question 21.
Draw diagrams to illustrate the positions of fulcrum, load and effort, in each of the following:
(a) a see saw
(b) a beam balance
(c) a nut cracker
(d) a pair of forceps
Answer:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 14

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 15

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 16

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 17

Question 22.
How can you increase the mechanical advantage of a lever ?
Answer:
The mechanical advantage of a lever can be increased by increasing the effort arm or reducing the load arm.

Question 23.
How does the friction at the fulcrum affect the mechanical advantage of the lever ?
Answer:
Friction at the fulcrum reduces the mechanical advantage.

Question 24.
State three differences between the three classes of levers.
Answer:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 18

Question 25.
What is a pulley ?
Answer:
Pulley: It is a flat circular disc with a groove in its edge and a rope passing through the groove. It is capable of rotating around a fixed point passing through its central axis called axle.

Question 26.
What is the mechanical advantage of an ideal pulley ?
Answer:
In an ideal pulley, the effort applied is equal to the load to be lifted.
i.e. Effort = Load
Mechanical advantage = Load / Effort = 1

Question 27.
The mechanical advantage of an actual pulley is less than 1. Give a reason. What is the justification for using the pulley then ?
Answer:
In an actual pulley due to friction, the mechanical advantage is less than 1 (i.e. the effort is more than the load).
The reason for using the pulley when its mechanical advantage is equal to 1 or less than 1 is that the pulley allows us to apply the effort downwards i.e. in a convenient direction. To raise a load directly upwards is difficult. But with the help of a pulley, the effort can be applied in the downward direction to move the load upwards. One can hang on it to make use of his own weight also in order to apply the effort.

Question 28.
Draw a neat labelled diagram showing a pulley being used to lift a load. How are load and effort related in an ideal situation?
Answer:
To raise a load, the load is attached to one end of the string and the effort is applied at the other end by pulling it is downward direction . as shown in fig.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 19

Question 29.
What is an inclined plane? What is its use ? Give two examples where ¡t is used.
Answer:
An inclined plane is a rigid sloping surface over which heavy loads can be raised or lowered to a certain height or depth.
The mechanical advantage of an inclined plane is the ratio of the length of the plank to the vertical height of the load raised. Its value is greater than one. Therefore, an inclined plane acts as a force multiplier. Thus, it can be used to lift heavy loads.
Example : If a heavy box needs to be loaded on a lorry, it is far easier to push it over an inclined plane than to lift it up. Steeper the inclined plane, greater will be the effort required to push up the load.
Sloping ramps, flyovers, roads on hills and staircases are all examples of inclined planes.

Question 30.
What is a screw ? Give two examples.
Answer:
A screw is a simple machine which appears like an inclined plane wound around a rod with a pointed tip.
Examples : ajar lid, a drill.

Question 31.
What is wheel and axle ? Give two examples.
Answer:
The wheel and axle is a simple machine having a wheel and an axle. The linear motion of axle is obtained by rotating the wheel so as to reduce friction. Example: Steering wheel, screw drivers, water tap etc.

Question 32.
How does a wheel help in moving the axle ?
Answer:
Wheel-and-axle arrangement consists of two cylinders of different diameters joined together such that if one is made to rotate, the other also rotates. The axle is a cylindrical rod fixed to the centre of a circular disc-like object called the wheel.
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 20
This machine acts as a speed multiplier device.
In riding a bicycle, when we apply force on the wheel (by pedal), the fixed axle rotates with it easily. This force that turns the axle produces a much larger movement of the wheel.

Question 33.
What is a wedge ? Give two examples.
Answer:
A wedge is a double inclined plane such that the two sloping surfaces taper to form either a sharp edge or a pointed edge. Examples : A knife, an axe, a chisel.
In some special cases, the number of inclined planes used can be more than two as well. In such cases, the sloping surfaces generally taper to form either a very sharp or a pointed edge to split or pierce materials. Pins, nails and needles are examples of pointed wedges. The front end of a boat is shaped like a wedge so that it can easily cut across the flowing water.
The wedge works on a principle of an inclined plane.

Question 34.
Name the machine to which the following belong :

  1. Beam balance
  2. Lemon crusher
  3. Sugar tongs
  4. Ramp
  5. Door knob
  6. Needle

Answer:

  1. Beam balance — A lever (lever of class I)
  2. Lemon crusher — A lever (lever of class II)
  3. Sugar tongs — A lever (lever of class III)
  4. Ramp — An inclined plane
  5. Door knob — Wheel and axle
  6. Needle — Wedge

Question 35.
What care would you take to increase the life span of a machine which you use ?
Answer:
Taking care of machines: Some of the ways in which machines should be cared for are given below :

  1. Machines should be kept in a clean environment, which is free from dust and moisture.
  2. When not in use, machines should be kept covered to prevent collection of dust on them.
  3. Machines made of iron should be protected from rust by coating them with paint.
  4. The moving parts of a machine should be regularly oiled with a good-quality machine oil to reduce friction and wear and tear. The above care of machines increases their life.

Question 36.
Select the correct statement :
(a) A wheel barrow is a lever of class I.
(b) The efficiency of a machine is always 100%
(c) Friction in moving parts of a machine reduces its efficiency.
(d) No lever has the mechanical advantage greater than 1.
(e) It is easier to lift a load vertically up than to push it along an inclined plane.
(f) A screw is made by two inclined planes placed together.
Answer:
(c) Friction in moving parts of a machine reduces its efficiency.

C. Numericals

Question 1.
In a machine an effort of 10 kgf is applied to lift a load of 100 kgf. What is its mechanical advantage ?
Answer:
Given,
Load = loo kgf
Effort = 10 kgf
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 21

Question 2.
The mechanical advantage of a machine is 5. How much load it can exert for the effort of 2 kgf ?
Answer:
Given,
Mechanical advantage = 5
Effort 2 kgf
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 22

Question 3.
The mechanical advantage of a machine is 2. It is used to raise a load of 15 kgf. What effort is needed ?
Answer:
Given,
Mechanical advantage = 2
Load = 15 Kgf
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 23

Question 4.
A lever of length 100 cm has effort of 15 kgf at a distance of 40 cm from the fulcrum at one end. What load can be applied at its other end ?
Answer:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 24

Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 25

Question 5.
In a lever, fulcrum is at one end at a distance of 30 cm from the load and effort is at the other end at a distance of 90 cm from the load. Find :
(a) the length of load arm,
(b) the length of effort arm, and
(c) the mechanical advantage of the lever.
Answer:
Selina Concise Physics Class 6 ICSE Solutions Chapter 4 Simple Machines 26

ICSE Solutions for Class 6 Geography Voyage – Minerals and Ores

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ICSE Solutions for Class 6 Geography Voyage – Minerals and Ores

ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions

APlusTopper.com provides step by step solutions for ICSE Solutions for Class 6 Geography Voyage. You can download the Voyage Geography ICSE Solutions for Class 6 with Free PDF download option. Geography Voyage for Class 6 ICSE Solutions all questions are solved and explained by expert teachers as per ICSE board guidelines.

ICSE Solutions Class 6 GeographyHistory & CivicsBiologyChemistryPhysicsMaths

POINTS TO REMEMBER

  • Minerals are substances that are naturally present in the earth and are not formed from animal or vegetable matter.
  • An ore is a naturally occurring solid material from which a mineral, generally a metal, can be profitably extracted.
  • Minerals are generally classified as metallic and non-metallic minerals.
  • Metallic minerals include iron ore, uranium, bauxite, manganese, gold, silver and copper.
  • Non-metallic minerals include limestone, mica, coal and petroleum.
  • Mining is the process of taking out minerals and other substances from the earth.
  • There are two types of mining—surface mining and underground mining.
  • It is important to conserve minerals as they take thousands of years to form.

IMPORTANT TERMS

Ferrous minerals : Minerals which contain iron, such as iron ore, manganese and chrome.
Non – ferrous minerals : Minerals that do not contain iron, such as gold, silver, copper and lead.
Ore : A naturally occurring solid material from which a particular mineral, usually a metal, can be profitably extracted.

THINK AND ANSWER

How would our life be affected if coal, petroleum and natural gas were exhausted in the next 30 years ?
Answer:
If all the exhaustible natural resources are exhausted by human activities, then the survival of living beings would not be possible. Actually, fossil fuels are the most important source of energy for us today.
They are concentrated source of energy and give offheat and light on burning. The heat can be used to cook food or to run engines such as automobile engines. It can be used to generate electricity as in powerhouse where the most common fuel used is coal. Everything will not be available.

VALUES AND LIFE SKILLS

Conventional energy resources—coal and petroleum— are very important for a country. Therefore, we need to be careful while using them.
Can you suggest some ways by which we can reduce the use of conventional energy resources ?
Answer:

  1. Use more energy efficient by using energy saver products like LED lights etc.
  2. Use Bicycles for shorter distances instead of cars or bikes.
  3. Switch off the lights when not required.

EXERCISES

A. Fill in the blanks

  1. All rocks are composed of minerals.
  2. Minerals are obtained by a process called mining.
  3. Metallic minerals are generally found in igneous rocks.
  4. Ferrous minerals contain iron.
  5. Peat has very little carbon.

B. Write true or false

1. Metals can be profitably extracted from ores.
Answer. True.

2. Metallic minerals are generally found in sedimentary rocks.
Answer. False.
Correct — Metallic minerals are generally found in igneous rocks.

3. Bauxite is the lightest metal.
Answer. True.

4. Bituminous coal has the highest carbon content.
Ans. False.
Correct — Anthracite coal has the highest carbon content.

5. Mica is a metallic mineral.
Ans. False.
Correct— Mica is a non-metallic mineral.

C. Match the columns
ICSE Solutions for Class 6 Geography Voyage Chapter 7 Minerals and Ores 1
Answer:
ICSE Solutions for Class 6 Geography Voyage Chapter 7 Minerals and Ores 2
ICSE Solutions for Class 6 Geography Voyage Chapter 7 Minerals and Ores 3

D. Answer the following questions in brief:

Question 1.
What is a mineral ?
Answer:
Minerals are substances that are naturally present in the earth and are not formed from animal or vegetable matter.

Question 2.
Name a few minerals.
Answer:
Diamonds, quartz, topaz, gypsum, iron, copper, bauxite, zinc, gold, silver, manganese, etc.

Question 3.
What is an ore ?
Answer:
An ore is a naturally occurring solid material that contains a large amount of a particular material, using a metal which can profitably extracted, eg. iron ores, copper ores, bauxite (from which aluminium is extracted) zinc, etc.

Question 4.
What is the main difference between a ferrous and a non- ferrous mineral ?
Answer:
Ferrous minerals :

  1. These minerals contain iron.
  2. They have high tensile strength.
  3. Examples: Iron ore, manganese and chrome.

Non-ferrous minerals :

  1. These minerals does not contain iron.
  2. They have low tensile strength.
  3. Examples: Gold, silver, copper and lead.

Question 5.
Mention any two characteristics of iron ore.
Answer:
The most important mineral in the world is iron ore. It is known for its hardness, strength and ductility (it can be made or stretched into a thin wire).

Question 6.
Mention the different types of iron ore.
Answer:
There are four different types of iron ores-haematite, magnetite, limoniteandsiderite.

Question 7.
What is surface mining ?
Answer:
When the top layer of soil is removed and the rocks that lie underneath are extracted with the help of heavy machinery is called surface mining. Surface mining is done to extract minerals that are found close to the surface such as coal and some kinds of sedimentary rocks like limestone and mica.

Question 8.
Mention any three uses of coal.
Answer:
Coal is used for various purposes like cooking, heating and producing electricity, and in various industries.

E. Answer the following questions in one or two paragraphs

Question 1.
Differentiate between metallic and non-metallic minerals.
Answer:
Metallic Minerals :

  1. These minerals contain metals, which are hard substances.
  2. These minerals found in igneous rocks.
  3. Examples: Iron ore, bauxtie, manganese and copper, etc.

Non-metallic Minerals :

  1. These minerals does not contain extractable metals.
  2. These minerals found in sedimentary rocks.
  3. Examples: Coal, potash, limestone, gypsum, mica, etc.

Question 2.
Give an account of iron ore production in the world.
Answer:
Iron is the main metal used for making steel, which is used in almost all industries. The main producers of iron are China (42%), Australia (22%), Brazil (10%), South Africa, etc. India produces about 4% of total iron ore. Main states in India are Odisha, MP, Jharkhand, AndhraPradesh, Tamil Nadu.

Question 3.
Give any three uses of copper.
Answer:
Uses of copper are :

  • Copper is mainly used in making electric and telephone wires.
  • It is also used in making pipes and coins.
  • Alloys such as brass and bronze are made using copper.

Question 4.
What are the two types of mining ? Elaborate on the differences between the two.
Answer:
The two types of mining are:

  1. Surface mining — It is the removal of top layer of soil and rocks, to extract the minerals lying underneath is called surface mining. Surface mining is done to extract minerals that are found close to the surface such as coal and some kinds of sedimentary rocks like limestone and mica.
  2. Underground mining — It is the one in which a shaft is dug which is long, narrow passage and vertically deep into the ground and then people or heavy machinery is sent down, the tunnels are blasted using dynamite to extract the minerals, eg. gold, silver, etc.
    In surface mining, the top layer of the soil is removed, large pits or holes are dug and the rocks that lie underneath are extracted with the help of heavy machinery. These pits are called open cast mines or quarries. Open cast mining is a common form of coal mining in India.
    In surface mining, trees and other natural vegetation are destroyed. Surface mining is done to extract minerals that are found close to the surface such as coal and some kinds of sedimentary rocks like limestone and mica.
    Underground mining: In underground mining, a shaft, which is a long, narrow passage, is dug vertically deep into the groud. People and machinery are then sent down through this shaft. Sometimes, after after descending into the shaft, tunnels are blasted into the earth with the help of dynamite. Then the men and machines move about through these tunnels to take out things such as coal, gold, silver, tin, lead and copper. Underground mining causes sinking of the land, underground water pollution and surface water pollution, among other things.

Question 5.
Describe the importance of minerals.
Answer:
Minerals play an important role in our daily lives. A number of things of our daily use such as door knobs, latches, window grills, utensils, etc. are made of minerals. Iron and its alloy, steel, is used in making bridges, buildings, and wide range of machines and tools, which have made our life simpler and easier. Copper wires are used in our electrical and electronic gadgets. Copper tools and utensils are also widely used. Gold and silver are used in making our jewellery. Aluminium extracted from bauxite is used to make aeroplanes, our fastest means of transport. Mica is used in electrical goods and limestone is used as cement in constructing houses and buildings.
Coal, petroleum and natural gas are important energy or power resources. Coal is used for various purposes like cooking, heating and producing electricity, and in various industries. Once petroleum is refined, we obtain different products such as petrol, diesel, kerosene, cooking gas, etc. Vehicles such as cars, trucks, trains, etc. run on petrol and diesel. Kerosene is used for cooking and other purposes. Products such as plastics and cosmetics are also made from petroleum. Natural gas is used as a fuel in cars, buses, etc. and hence are important for the agricultural sector as well.

Question 6.
Why is it important to conserve minerals ?
Answer:
Minerals are important for every country for its development and they need to be conserve because :

  1. Minerals are non-renewable resources which once used can’t be obtained again as it takes thousands of years to form.
  2. Workable minerals are in insufficient quantities (just 1 % of the earth’s crust)
  3. We are rapidly consuming mineral resources that requires millions of years to be renewed.
  4. Industry and agriculture depend upon minerals and the substances manufacture from them.

F. Picture study.
ICSE Solutions for Class 6 Geography Voyage Chapter 7 Minerals and Ores 4
Look at this picture of the inside of an iron and steel industry and answer the following questions

Question 1.
Which are the major producers of iron and steel in Asia?
Answer:
China produces almost 45 per cent of the total world production of Iron and Steel.

Question 2.
Which states in the south of India produce a large quantity of iron and steel ?
Answer:
Andhra Pradesh and Tamil Nadu are the major iron-producing states.