Question

In the figure given below, velocities of different blocks are shown. What will be the speed of block C, if pulleys are frictionless and strings are inextensible?

• A. $6m/s$
• B. $4m/s$
• C. $0m/s$
• D. None of these

Answer 1

The correct option is B $4m/s$

Velocity of pulley 1,
$V_{p_1}=\frac{V_A+V_B}{2}$
$V_{p_1}=\frac{-6+6}{2}=0$
Velocity of pulley 2 will be equal to that of pulley 1 since both are connected by same string that passes over a fixed pulley.
$|V_{p_2}|=|V_{p_1}|=0$
$\Rightarrow V_D=-V_C$
$\therefore$ Velocity of C is $=4m/s\uparrow$