Mark the correct statements for a particle going on a straight line:
(a) | if the velocity and acceleration have opposite sign, the object is slowing down. |
(b) | if the position and velocity have opposite sign, the particle is moving towards the origin. |
(c) | if the velocity is zero at an instant, the acceleration should also be zero at that instant. |
(d) | if the velocity is zero for a time interval, the acceleration is zero at any instant within the time interval. |
Choose the correct option:
1. | (a), (b) and (c) | 2. | (a), (b) and (d) |
3. | (b), (c) and (d) | 4. | all of these |
When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on the initial velocity and the braking capacity, or deceleration, that is caused by the braking. Expression for stopping distance of a vehicle in terms of and is:
1. | 2. | ||
3. | 4. |
A particle moves a distance in time according to equation The acceleration of the particle is proportional to:
1. (velocity)
2. (distance)
3. (distance)
4. (velocity)
1. | zero |
2. | constant |
3. | proportional to time |
4. | proportional to displacement |