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A long plank of mass M is initially at r...

A long plank of mass M is initially at rest on a frictionless surface. A small block with mass m and initial speed `u_(0)` slides on top of the larger plank. The coefficient of friction between the block and plank is `mu`

Net work done by friction if the top block falls off the plank after sliding over its length L is

A

`- mumgL`

B

`-mu((M+m)/(M))gL`

C

`-mu((M)/(M+m))gL`

D

`-mu MgL`

Text Solution

Verified by Experts

The correct Answer is:
A
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