Question

The net work done by the tension in the figure, when the bigger block of mass $M$ touches the ground is

• A. $+Mgd$
• B. $-(M+m)gd$
• C. $-mgd$
• D. Zero

Answer 1

The correct option is D Zero

Work done by tension on $M$ is negative (force and displacement are in opposite directions).
But work done by tension on $m$ is positive.
Magnitude of displacement is same for both masses.
Hence, net work done will be zero.