A block of mass m is released from the top of a wedge of mass M as shown in figure. Find the displacement of wedges on the horizontal ground when the block reaches the bottom of the wedges. Neglect friction everywhere.

Explanation

`l=hcostheta`
Let displacement of wedge be `x` towards right,

`/_\x_(CM)=(m(1+x)+Mx)/(M+m)`
`0=ml+(M+m)x`
`x=(-ml)/(M+m)=(mhcottheta)/(M+m)`