Question

Two blocks of masses 3kg and 6kg are connected by a light spring and placed on a smooth horizontal surface. Initially, the spring is unstretched and the 3kg block is given a velocity of 2m/s to the left as shown in the figure. Find the maximum velocity of 6kg block

• A. $\frac{7}{3}m/s$
• B. $\frac{5}{3}m/s$
• C. $\frac{4}{3}m/s$
• D. $\frac{2}{3}m/s$

Answer 1

The correct option is D $\frac{2}{3}m/s$

The maximum velocity of 6kg block will be at the instant when the spring has maximum elongation and both the blocks will be moving with same velocity equal to
$v=\frac{2\times 3}{3+6}=\frac{2}{3}m/s$