1. Derive the formula for work done by a constant force?

2. Give few examples where energy is possessed by a body due to its change in shape.?
3. State and prove the law of conservation of energy.?
4. Is it possible that force is acting on a body but still work done is zero? Explain.?
5. A rocket of mass3x106 kg takes off from a launching pad and acquires a vertical
velocity of 1km/s at an altitude of 25 km. calculate (a) the potential energy and (b) the
kinetic energy. (g = 9.8m/s2)?
6. A locomotive exerts a force of 7500N and pulls a train through 1.5 km. How much
work is done by locomotive?

Dear Student!!

Answer 1. 

A wooden block is kept on a table. When a force of magnitude F acts on the block, it gets displaced through a distance S in the direction of the applied force. 

The magnitude of work done is given by the product of force (F) and displacement (S).

Let W be the work done on the block.

∴ Work = Force × Displacement

Answer 2. 

There are many such kind of examples in which energy is possessed by a body due to its change in shape as,

Potential energy associated with the compression and expansion of spring.

Energy stored in the balloon when its compressed or being hit by an external force

Bending the bow etc.

Answer 3. Law of conservation of energy: Total energy of this universe is conserved (is constant). Energy cannot be created nor be destroyed. But can be transformed from one form to another.

For proof please refer the following link: https://www.meritnation.com/ask-answer/question/is-there-any-mathematical-proof-for-law-of-conservation-of-e/work-energy-and-power/1567032

Due to paucity of time it would not be possible for us to provide the answers to all your queries. Try solving rest of the questions yourself and if you face any difficulty then do get back to us.

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