In the figure,determine the type of collision. The masses of the blocks,and the velocities before and after the collision are given. The collision is

When two particles collide elastically,then impulsive force can't change

$A$ ball $A$ of mass $m$ moving along the positive $x$-direction with kinetic energy $K$ and momentum $p$ undergoes an elastic head-on collision with a stationary ball $B$ of mass $M$. After the collision,the ball $A$ moves along the negative $x$-direction with kinetic energy $K/9$. The final momentum of $B$ is:

In case of a perfectly elastic collision,

$A$ neutron moving with velocity $u$ collides elastically with an atom of mass number $A$. If the collision is head-on and the initial kinetic energy of the neutron is $E$, then the final kinetic energy of the neutron after the collision is:

$A$ neutron makes a head-on elastic collision with a stationary deuteron. The fractional loss of energy of the neutron in this collision is: