A cart of mass `M` is tied to one end of a massless rope of length `10 m`. The other end of the rope is in the hands of a man of mass `M`. The entire system is on a smooth horizontal surface. The man is at `x=0` and the cart at `x=10 m`. If the man pulls the cart by the rope, the man and the cart will meet at the point

Options

A. `x=0`
B. `x=5` m
C. `x=10` m
D. They will never meet

Answer

B

Explanation

If the man pulls the cart by the rope, then man and cart will meet at the centre of mass .
`x_(CM)=(m_(1)x_(1)+m_(2)x_(2))/(m_(1)+m_(2))=(Mxx0+Mxx10)/(M+M)=5m`