A boy of mass `m` is standing on a block of mass `M` kept on a rough surface. When the boy walks from left to right on the block, the centre of mass (boy + block) of system :

Options

A. remains stationary
B. shifts towards left
C. shift towards right
D. shift towards right if `M gt m` and towards left if `M lt m`.

Answer

C

Explanation

( c) As boy walk from left to right on the block, the block will recoil towards left. The friction acting on the block will act towards right. Hence the centre of mass of the boy and block will shift towards right.
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