Two block of masses `M_(1) and M_(2)` are connected with a string passing over a pulley as shown in figure The block `M_(1)` lies on a horizontal surface friction between the block `M_(1)` and the horizontal surface is `mu` The system accelerates. What additional mass `m` should be plased on the block `M_(1)` so that the system does not accelerate ?

Options

A. 12 kg
B. 11 kg
C. 10 kg
D. kg

Answer

B

Explanation

`T=M_(2)g=mu(M_(1)+m)g`
`therefore M_(2)=mu(M_(1)+m)`
`6=0.4(4+m)=11kg`.