A block of mass m moving at a velocity v collides with another block of mass \(2~\text m\) at rest. The lighter block comes to rest after collision. Find the coefficient of restitution.

1. \(\frac12\)                                          

2. \(1\)$\mathrm{}$

3. \(\frac13\)                                               

4. \(\frac 14\)

A spring \(40~\text {mm}\) long is stretched by the application of a force. If \(10 ~\text{N}\) force required to stretch the spring through \(1 ~\text{mm,}\) then work done in stretching the spring through \(40 ~\text{mm}\) is

1. \(84~\text{J}\)

2. \(68~\text{J}\)

3. \(23~\text{J}\)

4. \(8~\text{J}\)

Two springs with spring constants $k_1$ = 1500 N/m and $k_2$ = 3000 N/m are stretched by the same force. The ratio of potential energy stored in the springs will be 

1. 2:1

2. 1:2

3. 4:1

4. 1:4

A block of mass 2 kg moving with velocity of 10 m/s on a smooth surface hits a spring of force constant $80\times {10}^3$ N/m as shown. The maximum compression in the spring is

1. 5 cm

2. 10 cm

3. 15 cm

4. 20 cm

A particle of mass 10 kg is moving with velocity of $10\sqrt{x}$ m/s, where x is displacement . The work done by net force during the displacement of particle from x = 4 to x = 9 m is 

1. 1250 J

2. 1000 J

3. 3500 J

4. 2500 J

A body starts moving from rest in straight line under a constant power source. Its displacement in time t is proportional to

1. $t^{1/2}$

2. t

3. $t^{3/2}$

4. $t^2$

The relation between velocity (v) and time (t) is $v\propto \sqrt{\mathrm{t}}$, then which one of the following quantity is constant?

1.  Force

2.  Power

3.  Momentum

4.  Kinetic Energy

A particle is moving on the circular path of the radius (R) with centripetal acceleration $a_c=k^{2}R{t}^2$. Then the correct relation showing power (P) delivered by net force versus time (t) is 

1. 1

2. 2

3. 3

4. 4

A particle is moving in a vertical circle. The tension in the string when passing through two positions at angle of 30$°$ and 60$°$ from vertical (the lowest position) are ${\mathrm{T}}_1 \mathrm{and} {\mathrm{T}}_2$ respectively, then:

1.  ${\mathrm{T}}_1 = {\mathrm{T}}_2$

2.  ${\mathrm{T}}_2 < {\mathrm{T}}_1$

3.  ${\mathrm{T}}_2 > {\mathrm{T}}_1$

4.  Tension in the string always remains the same.

A body is thrown vertically up with a certain initial velocity. The potential and the kinetic energy of the body are equal at a point P in its path. If the same body is thrown with double the velocity upwards, the ratio of the potential and the kinetic energies of the body when it crosses at the same point will be: 

1. 1:1

2. 1:4

3. 1:7

4. 1:8