Question

In the figure shown, there is no friction between B and ground & $\mu =\frac{2}{3}$ between A and B; then:

• A. The net work done on block A with respect to B for a displacement S is zero.
• B. The net work done on block A with respect to ground for a displacement ‘S’ is $\frac{MgS}{3}$
• C. The net work done on block B with respect to ground for a displacement ‘S’ is $\frac{2MgS}{3}$
• D. The work done by friction with respect to ground on A & B is equal and opposite in sign.

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A

The net work done on block A with respect to B for a displacement S is zero.

B

The net work done on block A with respect to ground for a displacement ‘S’ is $\frac{MgS}{3}$

C

The net work done on block B with respect to ground for a displacement ‘S’ is $\frac{2MgS}{3}$

D

The work done by friction with respect to ground on A & B is equal and opposite in sign.

Both block will move together with acceleration $a=\frac{g}{3}$
W.D. on A for S displacement $=\frac{Mg}{3}S$
& W.D. on B for S displacement $=\frac{2Mg}{3}S$