Question

If both the blocks as shown in the given arrangement are given together a horizontal velocity towards right. If $a_{cm}$ be the subsequent acceleration of the centre of mass of the system of block then $a_{cm}$ equals?

• A. $0m/s^2$
• B. $\frac{5}{3}m/s^2$
• C. $\frac{7}{3}m/s^2$
• D. $2m/s^2$

Answer 1

The correct option is D $2m/s^2$

Acceleration of center of mass,

$a_{CM}=\frac{F_1+F_2}{m_1+m_2}=\frac{{\mu }_1{m}_{1}g+{\mu }_2{m}_{2}g}{1+2}$

=$\frac{(0.1\times 1\times 10)-(0.2\times 2\times 10)}{3}=\frac{6}{3}=2m/s^2$ (Taking g= 10m/$s^2$)