A particle $A$ is moving with a speed of $10\text{m/s}$ towards right and another particle $B$ is moving at speed of $12\text{m/s}$ towards left. Find their velocity of approach.

Q. A particle $A$ is moving with a speed of $20\text{m/s}$ towards right and another particle $B$ is moving at a speed of $5\text{m/s}$ towards right. Find their velocity of approach.

Q. A ball is moving with speed $12\text{m/s}$ towards a heavy wall which is moving towards the ball with the speed $10\text{m/s}$ as shown in figure. Assuming collision to be perfectly elastic, find the speed of ball after the collision.

Q. A particle $A$ is moving with a speed $10\text{m/s}$ towards right while particle $B$ is moving at a speed of $10\text{m/s}$ towards right and another particle $C$ is moving at speed of $10\text{m/s}$ towards left. The separation between $A$ and $B$ is $100\text{m}$. Find the time interval between $C$ meeting $B$ and $C$ meeting $A$.

Q. A particle $A$ is moving with a speed of $10\text{m/s}$ towards right and another particle $B$ is moving at speed of $12\text{m/s}$ towards left. Find their velocity of approach.

Q. A ball of mass $10\text{kg}$ is moving with a velocity of $10\text{m/s}$. It strikes another ball of mass $4\text{kg}$, which is moving in the same direction with a velocity of $4\text{m/s}$. If the collision is elastic their velocities after collision will be respectively