Question

The balloon,the light rope and the monkey shown in figure are at rest in the air.If the monkey reaches the top of the rope,by what distance does the balloon descend ? Mass of the balloon=M,mass of the monkey=m and the length of the rope ascended by the monkey=L.

Answer 1

Initilally the monkey anf balloon are at rest.

So,the C.M. is at 'P'.

When the monkey descends through a distance L,the c.m. will shift.

$t_0=\frac{m\times L+M\times 0}{M+m}$

$=\frac{mL}{M+m}$ from P

So,the balloon descends through a distance $=\frac{mL}{M+m}$.