A boy standing at the top of a tower of 20 m height drops a stone. Assuming g=$10 {\mathrm{ms}}^{-2}$, the velocity with which it hits the ground will be:
1. 20 m/s                                         
2. 40 m/s
3. 5 m/s                                           
4. 10 m/s

The motion of a particle along a straight line is described by the equation
         \(x=8+12 t-t^3\)

where \(x\) is in metre and t is in second. The retardation of the particle when its velocity becomes zero is:

A particle is projected upwards. The times corresponding to height h while ascending and while descending are t₁ and t₂ respectively. The velocity of projection will be:

1. gt₁

2. gt₂

3. $g$ $(t_1+t_2)$

4. $\frac{g(t_1+t_2)}{2}$

Four marbles are dropped from the top of a tower one after the other at a one-second interval. The first one reaches the ground after 4 seconds. When the first one reaches the ground the distances between the first and second, the second and third, and the third and fourth will be, respectively:

The acceleration of a particle starting from rest varies with time according to the relation A = – aω²sinωt. The displacement of this particle at a time t will be:

1. $-\frac{1}{2}\left({\mathrm{a\omega }}^2\mathrm{sin\omega t}\right){\mathrm{t}}^2$

2. $\mathrm{a\omega sin\omega t}$

3. $\mathrm{a\omega cos\omega t}$

4. $\mathrm{asin\omega t}$

Given below are two statements: 

Acceleration-time graph of a body is shown.

 
The corresponding velocity-time graph of the same body is: 

1.		2.
3.		4.

Which of the following velocity-time graphs shows a realistic situation for a body in motion?

1.		2.
3.		4.

Which graph represents a uniformly accelerated motion?

1.		2.
3.		4.

In the following graph, the distance travelled by the body in metres is: