A particle moves around a circle with a unique uniform speed in each revolution. After the first revolution and during the \(2\)nd revolution: its speed doubles; and during the \(3\)rd revolution, its speed becomes \(3\) times the initial speed and so on. The time for the \(1\)st revolution is \(12\) sec. The average time per revolution, for the first four revolutions, is:
1. \(4.8\) s
2. \(9.6\) s
3. \(6.25\) s
4. \(6\) s
Assertion (A): | The average speed of a particle that has undergone motion can be zero, but its average acceleration cannot be zero. |
Reason (R): | The average speed is the distance travelled per unit time over the entire motion, while the average acceleration is the change in velocity divided by the time. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
1. | \(25~\text{km/h}\) | 2. | \(24~\text{km/h}\) |
3. | \(27~\text{km/h}\) | 4. | \(28~\text{km/h}\) |
Assertion (A): | If \(u_{\Large_A}>u_{\Large_B}\) then \(v_{\Large_B}>v_{\Large_A}\) and vice-versa. |
Reason (R): | Since they traverse the same distance in the same time \((T),\) their average velocities must be equal: the average velocity being the mean of the initial and final velocities. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |