A block having mass $m$ collides with an another stationary block having mass $2\,m$. The lighter block comes to rest after collision. If the velocity of first block is $v$, then the value of coefficient of restitution will must be

A body of mass $5\,kg$ strikes another body of mass $2.5\,kg$ initially at rest. The bodies after collision coalesce and begin to move as a whole with a kinetic energy of $5\,J$. The kinetic energy of the first body before collision is ............... $\mathrm{J}$

A particle of mass $m$ is moving with speed $2\, v$ collides with a mass $2\,m$ moving with speed $v$ in the same direction. After collision, the first mass is stopped completely while the second one splits into two particles each of mass $m$, which move at angle $45^o$ with respect to the original direction. The speed of each of the moving particle will be

Explain oblique collision.

$A$ chain of length $L$ and mass $m$ is placed upon a smooth surface. The length of $BA$ is $L-b$. Calculate the velocity of the chain when its end reaches $B$.

A moving particle of mass $m,$ makes a head on elastic collision with another particle of mass $2\,m,$ which is initially at rest. The percentage loss in energy of the colliding particle on collision, is close to .................. $\%$