Question

A coolie $X$ carrying a load on his head climbs up on slope and another coolie $Y$ carrying the identical load on his head moves the same distance on a friction less horizontal platform. Who does more work?

• A. X
• B. Y
• C. Both A & B
• D. Cannot say

Answer 1

The correct option is A X

As work is given by formula $W=F\times s\times cos\theta$.

Here in case of $Y$, angle between force and displacement is $90$ degree. Hence work becomes zero that is coolie $Y$ is doing zero work.

Whereas in case of $X$, force and displacement are not perpendicular. Hence, coolie $X$ is doing some work. Coolie $X$ does work against force of gravity while coolie $Y$ does no work because displacement is normal to the force of gravity.