Question

Two blocks (of masses $400kg$ and $30kg$) are attached to the two ends of a string passing over a smooth pulley as shown in the figure. The acceleration of the block will be (in $m/s^2$) ?

• A. $6.33$
• B. $5.02$
• C. $4$
• D. $3.66$

Answer 1

Answer: (B)

$5.02$

As the pulley is smooth, the magnitude of acceleration of both blocks are equal.

For $400kg$ : $400a=400g\sin 37-T...\left(1\right)$

For $30kg$ : $30a=T-30g\sin 53....\left(2\right)$

Adding $\left(1\right)$ and $\left(2\right)$,

$430a=400g\sin 37-30g\sin 53=2226.7$

$\therefore a=5.02m/s^2$