Question

A hanging mass $M$ is connected to a four times bigger mass by using a string-pulley arrangement, as shown in figure. the bigger mass is placed on a horizontal ice-slab and being pulled by $2Mg$ force. In this situation, tension in the string is $\frac{x}{5}Mg$ for $x=$
Neglect mass of the string and friction of the block (bigger mass) with ice slab. (Given g = acceleration due to gravity)

Answer 1

Acceleration of block:
$a=\frac{Mg}{4M+M}=\frac{g}{5}$ (in upward direction)
Force balance (hanging mass)
$T=M(g+\frac{g}{5})=\frac{6Mg}{5}$
$\Rightarrow x=6$