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 |
| 1. | \(1:4\) | 2. | \(4:1\) |
| 3. | \(2:1\) | 4. | \(16:1\) |

| 1. | \(\dfrac{m'}{m}=\dfrac{1}{10}\) | 2. | \(\dfrac{m'}{m}=\dfrac{1}{9}\) |
| 3. | \(\dfrac{m'}{m}=\dfrac{1}{8}\) | 4. | \(\dfrac{m'}{m}=\dfrac{1}{2}\) |
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. | \(\dfrac{15}{\sqrt{2}}~\text{m/s}\) |
| 1. | \(v\) | 2. | \(\dfrac{v}{2}\) |
| 3. | \(\dfrac{v}{3}\) | 4. | \(\dfrac{v}{4}\) |
A body at rest breaks into two pieces of equal masses. The parts will move:
| 1. | in the same direction. |
| 2. | along different lines. |
| 3. | in opposite directions with equal speeds. |
| 4. | in opposite directions with unequal speeds. |