A particle starts to move in a straight line from a point with a velocity 10 ms^-1 and acceleration -2.0 ms^-2. Its position at t = 5 s will be :

1. 5 m
2. 10 m
3. 20 m
4. 25 m

A body initially at rest, starts moving with a constant acceleration of 0.5 ms^-2 and travels a distance 25 m, then its final velocity is:

1. 5 ms^-1
2. 20 ms^-1
3. 15 ms^-1
4. -15 ms^-1

A car starting from rest moves on a straight path for time t = 0 to t = T with a uniform acceleration a and then stops with a uniform retardation. The average speed of the car will be :

1. $\dfrac{\text {aT}}{4}$

2. $\dfrac{3\text {aT}}{2}$

3. $\dfrac{\text {aT}}{2}$

4. aT

Assertion (A) : The displacement of a body can be zero even if the distance travelled by it is not zero.

Reason (R) : Displacement is the shortest distance from the initial to the final position of body.

1. both A and R are true and R is the correct explanation of A
2. both A and R are true and R is not the correct explanation of A
3. assertion is false but reason is true
4. assertion is true but reason is false