Q. No.Two identical balls A and B are moving with velocity and respectively. If they collide head on elastically, then their velocities after collision will be:
1.
2.
3.
4.
Two equal masses initially moving along the same straight line with velocity \(+4\) m/s and \(-5\) m/s respectively collide elastically. Their respective velocities after the collision will be:
| 1. | \(-5\) m/s and \(+3\) m/s | 2. | \(+4\) m/s and \(-4\) m/s |
| 3. | \(-4\) m/s and \(+4\) m/s | 4. | \(-5\) m/s and \(+4\) m/s |
The momentum of the system, as a result of the collision:
1. increases
2. decreases
3. remains constant
4. decreases suddenly and then increases
A bomb of mass 30kg at rest explodes into two pieces of masses 18 kg and 12 kg. The velocity of 18kg mass is 6ms–1. The kinetic energy of the other mass is:
1. 524 J
2. 256 J
3. 486 J
4. 324 J
| 1. | \(1:4\) | 2. | \(4:1\) |
| 3. | \(2:1\) | 4. | \(16:1\) |
If the coefficient of restitution for the collision is \(e=\dfrac12,\) the final relative speed between the blocks is:
1. \(3~\text{m/s}\)
2. \(2~\text{m/s}\)
3. \(1.5~\text{m/s}\)
4. \(1~\text{m/s}\)
| 1. | \(\dfrac{m'}{m}=\dfrac{1}{10}\) | 2. | \(\dfrac{m'}{m}=\dfrac{1}{9}\) |
| 3. | \(\dfrac{m'}{m}=\dfrac{1}{8}\) | 4. | \(\dfrac{m'}{m}=\dfrac{1}{2}\) |
1. \(46\)
2. \(384\)
3. \(192\)
4. \(768\)
A \(5\) kg stationary bomb explodes in three parts with masses in the ratio \(1:1:3\) respectively. If parts having the same mass move in perpendicular directions with velocity \(30\) m/s, then the speed of the bigger part will be:
| 1. | \(10\sqrt{2}~\text{m/s}\) | 2. | \(\dfrac{10}{\sqrt{2}}~\text{m/s}\) |
| 3. | \(13\sqrt{2}~\text{m/s}\) | 4. | \(\dfrac{15}{\sqrt{2}}~\text{m/s}\) |
The relative velocity between the blocks, after the collision, has the magnitude:
| 1. | \(2~\text{m/s}\) | 2. | \(1~\text{m/s}\) |
| 3. | \({\Large\frac12}~\text{m/s}\) | 4. | \({\Large\frac14}~\text{m/s}\) |
© 2026 GoodEd Technologies Pvt. Ltd.