Question

Two blocks each having a mass $M$ are placed as shown in the figure. The acceleration of the system is:

• A. $0$
• B. $\frac{g\sin \theta }{2}$
• C. $g\sin \theta$
• D. $2g\sin \theta$

Answer 1

Answer: (B)

$\frac{g\sin \theta }{2}$

Let common acceleration of the system is $a$

FBD of mass $m$ inclined at an angle $\theta$
$mgsin\theta -T=ma...\left(1\right)$
and FBD of block lying on surface
$\Rightarrow T=ma...\left(2\right)$
from (1) and (2) $mgsin\theta =2ma\Rightarrow a=\frac{g}{2}sin\theta$