1. | distance travelled in last second of downward journey |
2. | distance travelled in first second of upward journey |
3. | distance travelled in first second of downward journey |
4. | both (1) and (2) |
A particle is moving along a straight line such that its position depends on time as \(x=1-at+bt^{2} \), where \(a=2~\text{m/s}\), \(b=1~\text{m/s}^2\). The distance covered by the particle during the first \(3\) seconds from start of the motion will be:
1. | \(2~\text{m}\) | 2. | \(5~\text{m}\) |
3. | \(7~\text{m}\) | 4. | \(4~\text{m}\) |
1. | \(1: \sqrt{3}\) | 2. | \(\sqrt{3}: 1\) |
3. | \(1:1\) | 4. | \(1:2\) |
Assertion (A): | Adding a scalar to a vector of the same dimension is a meaningful algebraic operation. |
Reason (R): | Displacement can be added to distance. |
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. | Both (A) and (R) are False. |
Assertion (A): | A particle having zero acceleration must have a constant speed. |
Reason (R): | A particle having constant speed must have zero acceleration. |
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. | Both (A) and (R) are False. |
Assertion (A): | A body can have acceleration even if its velocity is zero at a given instant of time. |
Reason (R): | A body is momentarily at rest when it reverses its direction of motion. |
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. | Both (A) and (R) are False. |
Assertion (A): | If the average velocity of a particle is zero in a time interval, it is possible that the instantaneous velocity is never zero in the interval. |
Reason (R): | If the average velocity of a particle moving on a straight line is zero in a time interval then at least for one moment the instantaneous velocity will also be zero in the interval. |
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. | Both (A) and (R) are False. |