Question

Find the velocity of block $A$ i.e. $v_A$ in the shown figure.

• A. $v_A=\frac{v}{5}$, upward
• B. $v_A=5v$, upward
• C. $v_A=\frac{v}{5}$, downward
• D. $v_A=5v$, downward

Answer 1

The correct option is A $v_A=\frac{v}{5}$, upward

Let the velocity of block $A$ be $v_A$ upward

As we know that, the string's end attached to the fixed pulley will have zero velocity. So, considering the points $1$ to $6$ in the figure, we have
$-v_A-v_A-v_A-v_A-v_A+v=0$
$\Rightarrow 5v_A=v\Rightarrow v_A=\frac{v}{5}$
Hence, velocity of block $A$ is $v_A=\frac{v}{5}$, upward.