What are the various energy transformations that occur when you are riding a bicycle?

The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?

A mass of 10 kg is at a point A on a table. It is moved to a point B. If the line joining A and B is horizontal, what is the work done on the object by the gravitational force? Explain your answer.

Certain force acting on a 20 kg mass changes it's velocity from 5 ms–1 to 2 ms–1. Calculate the work done by the force.

A battery lights a bulb. Describe the energy change involved in the process.

An object thrown at a certain angle to the ground moves in a curved path and fall back to the ground. The initial and the final points of the path of the object lie on the same horizontal line. What is the work done by the force of gravity on the object.