Question

A coolie moves on a horizontal platform with luggage on his head. The work done by coolie on the luggage is zero. (T or F)

• A. True
• B. False

Answer 1

The correct option is A True

1. In this case, the direction of the displacement is in the horizontal direction, whereas the direction of the force on the luggage by the coolie is in the vertical direction.
2. So the force and displacement are perpendicular to each other which implies that the angle between them is $90°$.
3. As $\cos 90°=0$, applying this to the formula for work done would result in zero.

Hence, the work done by the coolie on the luggage is zero.