# Class 10 FRANK Solutions Physics Chapter 1.5 - Different Forms, Conservation and Transformation of Energy

Revise from accurate Frank Solutions for ICSE Class 10 Physics Chapter 1.5 Different Forms, Conservation and Transformation of Energy at TopperLearning. Learn the SI unit of energy. Understand the parameters that can change kinetic energy. Also, revise the concept of potential energy with our well-prepared Physics solutions.

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## Different Forms, Conservation and Transformation of Energy Exercise 53

### Solution 1

The energy possessed by a body by virtue of its motion is called kinetic energy.

### Solution 2

Examples of kinetic energy:

(i) Air in motion has kinetic energy.

(ii) A swinging pendulum

(i) Air in motion has kinetic energy.

(ii) A swinging pendulum

### Solution 3

SI unit of energy is 'joule'.

### Solution 4

Work

### Solution 5

'Energy' is the body's ability to do work.

### Solution 6

Energy is a scalar quantity.

### Solution 7

### Solution 8

Kinetic energy of a body depends upon:

(i) Mass of the body

(ii) Speed of the body

(i) Mass of the body

(ii) Speed of the body

### Solution 9

Yes, if the body is not in motion; it has zero kinetic energy

### Solution 10

A moving bullet possesses kinetic energy

### Solution 11

### Solution 12

### Solution 13

Flowing water possesses kinetic energy.

### Solution 14

### Solution 15

The car should be moving faster because the mass of the car is less than that of the bus.

### Solution 16

Its kinetic energy changes with the change in velocity.

Velocity becomes zero at the highest point.

Velocity becomes zero at the highest point.

### Solution 17

### Solution 18

### Solution 19

The parameters that can change the kinetic energy are:

(i) Mass

(ii) Speed

(i) Mass

(ii) Speed

### Solution 20

A ball at lying at rest on the floor possesses zero kinetic energy.

### Solution 21

The energy possessed by a body by virtue of its position, shape or change of configuration is called potential energy.

### Solution 22

Potential energy of a body depends upon:

(i) Mass of the body

(ii) Acceleration due to gravity

(iii) Height of the body

(i) Mass of the body

(ii) Acceleration due to gravity

(iii) Height of the body

### Solution 23

### Solution 24

Examples of potential energy:

(i) Water stored at a height in a reservoir.

(ii) A stretched spring.

(i) Water stored at a height in a reservoir.

(ii) A stretched spring.

### Solution 25

P.E of a body lying on a floor is zero.

### Solution 26

The energy spent by the heart in pumping blood through the body is 1 J per beat.

### Solution 27

Potential energy

### Solution 28

The work done in winding a clock spring is stored as P.E. in the spring. This P.E. is then used to run the hands of the clock.

### Solution 29

P.E. of a body of mass M and at a height H above the earth's surface is:

P.E. = MgH ; here, g = acceleration due to gravity.

P.E. = MgH ; here, g = acceleration due to gravity.

### Solution 30

P.E. is a scalar quantity.

### Solution 31

(i) Potential energy

(ii) Heat energy

(iii) Potential energy

(ii) Heat energy

(iii) Potential energy

### Solution 32

(i) At the height H because the height is maximum.

(ii) At the ground level because the velocity is maximum.

(iii) At half distance of the total path i.e. at height H/2, the P.E. is equal to the K.E.

(ii) At the ground level because the velocity is maximum.

(iii) At half distance of the total path i.e. at height H/2, the P.E. is equal to the K.E.

### Solution 33

(a) As the height above the ground increases, the potential energy also increases.

(b) At the highest point, the height of the cricket ball is maximum and hence the potential energy is also maximum.

(b) At the highest point, the height of the cricket ball is maximum and hence the potential energy is also maximum.

## Different Forms, Conservation and Transformation of Energy Exercise 54

### Solution 34

P.E. is the energy possessed by a body by virtue of its position, shape or configuration but K.E. is the energy possessed by a body by virtue of its velocity or motion.

E.g. A ball kept on a cliff possesses P.E. but as soon as it is kicked it possesses K.E.

E.g. A ball kept on a cliff possesses P.E. but as soon as it is kicked it possesses K.E.

### Solution 35

Whenever one form of energy dissipates or disappears, another form of equivalent amount of energy is produced; this is referred to as transformation of energy.

E.g. when a particular switch is pressed electric lamps light up owing to the heat produced in the filament. This is the transformation of electrical energy to heat and light energy.

E.g. when a particular switch is pressed electric lamps light up owing to the heat produced in the filament. This is the transformation of electrical energy to heat and light energy.

### Solution 36

No, total energy of a body does not remain constant but the total energy of a closed system remains constant e.g. universe.

### Solution 37

Energy is a scalar quantity.

### Solution 38

No, we cannot destroy energy associated with a body.

### Solution 39

Energy is the capacity or ability of a body to do work or energy is stored work.

### Solution 40

The law of conservation of energy states that energy cannot be created or destroyed; the sum total of energy in a closed system remains unchanged. Energy only changes from one form to another.

### Solution 41

A dry cell converts chemical energy into electrical energy.

### Solution 42

A D.C. motor converts electrical energy into mechanical energy.

### Solution 43

A dynamo converts mechanical energy into electrical energy.

### Solution 44

Four different forms of energy:

(i) Solar energy

(ii) Mechanical energy

(iii) Wind energy

(iv) Nuclear energy

(i) Solar energy

(ii) Mechanical energy

(iii) Wind energy

(iv) Nuclear energy

### Solution 45

At a thermal power station, nuclear energy is converted into electrical energy.

### Solution 46

(i) Electrical energy to sound energy

(ii) Mechanical energy into heat energy.

(iii) Potential energy into kinetic energy and vice-versa.

(iv) Chemical energy obtained from food is converted into mechanical energy and heat energy in muscles.

(v) A dynamo converts mechanical energy into electrical energy.

(ii) Mechanical energy into heat energy.

(iii) Potential energy into kinetic energy and vice-versa.

(iv) Chemical energy obtained from food is converted into mechanical energy and heat energy in muscles.

(v) A dynamo converts mechanical energy into electrical energy.

### Solution 47

The rate of doing work is called power.

### Solution 48

'Watt' is the SI unit of power.

### Solution 49

Horse power is the unit of power. The horsepower used for electrical machines is defined as exactly 746 watt.

Classically, a horse exerting 1 H.P. can raise 330 pounds of coal 100 feet in a minutes, or 33 pounds of coal 1,000 feet in one minute, or, 1,000 pounds 33 feet in one minute.

Classically, a horse exerting 1 H.P. can raise 330 pounds of coal 100 feet in a minutes, or 33 pounds of coal 1,000 feet in one minute, or, 1,000 pounds 33 feet in one minute.

### Solution 50

If 1 joule of work is done in 1 second, the power is said to be 1 watt.

1 H.P. = 746 watt

1 H.P. = 746 watt

### Solution 51

### Solution 52

Power is the physical quantity associated with the 'rate of doing work'.

### Solution 53

### Solution 54

Practical or commercial unit of power is kilowatt-hour.

### Solution 55

When we wind a watch, the configuration of its spring is changed. The energy stored in the spring is obviously potential in nature (elastic potential to be more accurate).

### Solution 56

This heat energy comes from the mechanical energy.

### Solution 57

When we rub our hands, mechanical energy is converted into heat energy.

### Solution 58

When the head of a nail is struck with a hammer, the mechanical energy of the hammer pushes the nail into the plank of wood and in this process a part of energy is converted into heat energy.

### Solution 59

### Solution 60

### Solution 61

### Solution 62

### Solution 63

Examples of energy degradation: -

- When we run a vehicle, only a part of energy obtained from its fuel is used up in running the vehicle, major part of it is wasted in heating the moving parts of machine, in doing work against friction between the ground and its tyres and in the form of sound.
- In electric fan, some amount of electrical energy used to run motor (converting electrical energy to mechanical energy) is lost as heat energy and hence does not do any productive work in this case.