The expression of power P is:

1. P = mgh
2. P = $\dfrac{\text{1}}{\text{2}}$ mv²
3. P = F x d
4. P = F x $\dfrac{\text{d}}{\text{t}}$

1 H.P. is equal to:

1. 1 W
2. 1 J
3. 764 J
4. 746 W

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