Question

Rahul takes 1 minute to raise a box to a height of 1 metre and Rohan takes $\frac{1}{2}$ minute to do so. Comment on the energy spent by the two.

• A. Energy spent by the Rahul is more.
• B. Energy spent by both Rahul and Rohan is same.
• C. Energy spent by the Rohan is more
• D. Energy spent by both is zero

Answer 1

The correct option is B Energy spent by both Rahul and Rohan is same.

Energy spent by both Rahul and Rohan is the same which will be the potential energy whose magnitude is given by mgh
where m is the mass, g is the acceleration due to gravity and h is the height.
As they have done some work i.e., "mgh" in raising the body so there will be some amount of energy spent. Hence, the energy spent by both cannot be zero.
Note: Potential energy is independent of time.