A boy lifts a luggage from height 2 m to 4 m. The potential energy will become:

1. half
2. double
3. one-third
4. one-fourth

Whenever mechanical energy changes to other forms, it is always in the form of …………… energy and not in the form of …………… energy.

1. potential, kinetic
2. heat, potential
3. kinetic, potential
4. potential, heat

Assertion (A) : The power spent in doing a work remains the same, even if the same work is done in a lesser time.

Reason (R) : The power spent by a source depends on the time taken by the source to do that work.

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true and R is not the correct explanation of A
3. Assertion is true but reason is false
4. Assertion is false but reason is true

Assertion (A) : When a ball is dropped from a height, its kinetic energy decreases and potential energy increases.

Reason (R) : The total mechanical energy remains conserved during the fall, if we ignore air resistance.

1. Both A and R are true and R is the correct explanation of A
2. Both A and R are true and R is not the correct explanation of A
3. Assertion is true but reason is false
4. Assertion is false but reason is true