Question

Consider three systems, each with three masses, $m_{1},m_{2},m_{3}\left(m_{1} > m_{2} > m_{3}\right)$ with centre of mass at point $A,$ as shown in the figure - $1,$ figure - $2$ and figure - $3$ respectively. The same force $\overset{ \rightarrow }{F}$ is applied on the each system separately to just one of the three masses as shown. Which of the following statements is true.

• A. The magnitude of acceleration of centre of mass of the system is largest in figure - $1$ .
• B. The magnitude of acceleration of centre of mass of the system is largest in figure - $2$ .
• C. The magnitude of acceleration of centre of mass of the system is largest in figure - $3$ .
• D. In all cases, the centre of mass of system has same acceleration.

Answer 1

Answer: (D)

$\overset{ \rightarrow }{a}_{CM}=\frac{\overset{ \rightarrow }{F}_{net}}{\Sigma m i}$