If the system is released, then the acceleration of the centre of mass of the system is :
.

Options

A. `(g)/(4)`
B. `(g)/(2)`
C. g
D. 2 g

Answer

A

Explanation

(a) `a = (3m - m)/(3m + m) g = (g)/(2)`
`a_(cm) = (3a + 3m(-a))/(m + 3m)`
=`(-2 ma)/(4 m) = -(a)/(2) = -(g)/(4)`.
.