Question

The velocity of block $B$ just after collision is-

• A. $v_0$
• B. $\frac{v_0}{2}$
• C. $\frac{3v_0}{5}$
• D. $\frac{2v_0}{5}$

Answer 1

The correct option is B $\frac{v_0}{2}$

Just after collision there will be not a appreciable change in velocity of block A as it is connected by spring to block B. But the block B and Block C will be start moving with same velocity. Let this velocity be v.

So by conservation of momentum of block B and C

2mv${}_0$= 4mv

Which gives v= $\frac{v_0}{2}$