Question

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

• A. $g/4$
• B. $g/2$
• C. $g$
• D. $2g$

Answer 1

Answer: (A)

Acceleration of the system, $a=\frac{3m-m}{3m+m}g=\frac{g}{2}$
Acceleration of centre of mass, $a_{CM}=\frac{3m\times \frac{g}{2}-\frac{mg}{2}}{3m+m}=\frac{g}{4}$