DAV Class 6 Science Chapter 10 Solutions

DAV Class 6 Science Chapter 10 Solutions Work and Energy are prepared by subject experts. With the help of these solutions for Class 6 Science the Living World book, you can easily grasp basic concepts better and faster. Moreover, it is a perfect guide to help you to score good marks in school examination.

DAV Class 6 Science Chapter 10 Solutions Work and Energy

Highlights

• A. Fill in the blanks.
• B. True or False.
• C. Tick the correct option.
• D. Answer the following questions in brief.
• E. Answer the following questions.

A. Fill in the blanks.

1. The work done depends upon the ___________ applied and the ___________ produced.

2. ___________ is the capacity to do work.

3. ___________ energy, stored in a battery, can be used to produce light in a torch.

4. ___________ is the main source of light energy.

5. An electric bell produces sound from ___________ energy.

Answer: (1) force, displacement (2) Energy (3) Chemical (4) Sun (5) electrical

B. Write True or False for the following statements.

1. Work is done whenever a force is applied on a given object.

2. A stationery ball does not possess kinetic energy.

3. A ball, raised to a height, is said to possess chemical energy.

4. The motion, of the blades of a fan, is due to mechanical energy.

5. Sound is a form of energy.

Answer: (1) True (2) True (3) False (4) False (5) True

C. Tick the correct option.

Answer:

1. just holding a book in your hand for two minutes.

2. energy

3. kinetic energy

4. kinetic energy

5. potential energy

D. Answer the following questions in brief.

1. Write the meaning of the following terms.

(a) work

(b) energy

Answer:

(a) work – an activity involving a force and a net displacement in the direction of the applied force.

(b) Energy – capacity to do work is known as energy. 

2. State the conditions under which work is said to have been done.

Answer: Condition under which work is said to have been done are –

(a) Force to be applied 

(b) Displacement should be produced in the direction of applied force.

3. Name any three different forms of energy.

Answer: Three different forms of energy are – (a) Light energy (b) sound energy (c) chemical energy

4. State the type of mechanical energy possessed by the following:

(a) a bullet fired from a gun.

(b) the wound-up spring of a toy car.

(c) the water, stored at a height, in a tank.

(d) a moving bus.

Answer:

(a) Kinetic energy

(b) potential energy

(c) Potential energy 

(d) Kinetic energy

5. State two different uses of light energy.

Answer: Two different uses of light energy are – 

(a) Light energy of the sun is used by green plants to make their food.

(b) Light energy of the sun is used by solar cells to produce electricity.

E. Answer the following questions.

1. Is there a difference between ‘applying a force’ and ‘doing work’? Give reason for your answer.

Answer: Yes, because when we push or pull, we are applying force. But when displacement produced by an applied force, we are doing work.

2. Explain, by giving an example, that a moving object can do work.

Answer: A moving object possess energy and energy is the capacity to do work. So, we Can Say that a moving object can do work. 

Example: A fast moving ball can break a window glass.

3. A porter keeps standing at a place while holding a suitcase of mass 20 kg over his head for five minutes. Has he done some work? Give reason for your answer.

Answer: No, the porter has not done any work because displacement is zero here as the porter is standing at a place.

4. Define the term ‘energy’. Describe an activity to show the inter-relationship between work and energy.

Answer: Energy is capacity to do work. Work and energy are interrelated to each other. Work is done on an object when energy is transferred to that object. For example – when we push a cart, we use our muscular energy and work is done on the cart as it moves.

5. Name a device which converts

(a) electrical energy into light energy.

(b) sound energy into electrical energy.

(c) chemical energy into electrical energy.

Answer: 

(a) Electric bulb

(b) Microphone 

(c) Battery