Collision Examples I

Q. In an elastic collision

1. The kinetic energy first increases then decreases.
2. The initial kinetic energy is equal to the final kinetic energy
3. The final kinetic energy is less than the initial kinetic energy
4. The kinetic energy remains constant

Q. In an inelastic collsion

1. The initial kinetic energy is equal to the final kinetic energy
2. The final kinetic energy is less than the initial kinetic energy
3. The kinetic energy remains the constant
4. The kinetic energy first increases then decreases.

Q. A metal ball of mass $2\text{kg}$ moving with speed of $36\text{kmph}$ is having a collision with a stationary ball of mass $2\text{kg}$. If after collision, both the balls move together, the loss in kinetic energy due to collision is:

1. $60\text{J}$
2. $160\text{J}$
3. $80\text{J}$
4. $40\text{J}$

Q. After a totally inelastic collision, two objects of the same masses and same initial speeds are found to move together at half of their initial speeds as shown in figure below. If $\alpha ={30}^{\circ }$, then the angle between the initial velocities of the objects is

1. ${90}^{\circ }$
2. ${60}^{\circ }$
3. ${150}^{\circ }$
4. ${45}^{\circ }$

Q. A body of mass $2\text{kg}$ moving with a velocity $3\text{m/s}$ collides with a body of mass $1\text{kg}$ moving with a velocity of $4\text{m/s}$ in opposite direction. If the collision is head on and completely inelastic, then

1. Both particles move together with velocity $\left(\frac{2}{3}\right)\text{m/s}$
2. The momentum of system is $2\text{kg m/s}$ throughout
3. The momentum of system is $10\text{kg m/s}$
4. The loss of KE of system is $\left(\frac{49}{3}\right)J$

Q. In an inelastic collsion

1. The initial kinetic energy is equal to the final kinetic energy
2. The final kinetic energy is less than the initial kinetic energy
3. The kinetic energy remains the constant
4. The kinetic energy first increases then decreases.

Q. In an elastic collision

1. The initial kinetic energy is equal to the final kinetic energy
2. The final kinetic energy is less than the initial kinetic energy
3. The kinetic energy remains constant
4. The kinetic energy first increases then decreases.

Q. Two identical balls of masses $5\text{kg}$ each are kept on a frictionless surface as shown in the figure below. One of the balls moving at $4\text{m/s}$ makes a head-on collision with the other at rest initially. It is observed that final kinetic energy of the balls is half of the initial kinetic energy. Find the coefficient of restitution.

1. $e=0$
2. $e=1$
3. $e>1$
4. $0<e<1$

Q. A body of mass $2\text{kg}$ moving with a velocity $3\text{m/s}$ collides with a body of mass $1\text{kg}$ moving with a velocity of $4\text{m/s}$ in opposite direction. If the collision is head on and completely inelastic, then

1. Both particles move together with velocity $\left(\frac{2}{3}\right)\text{m/s}$
2. The momentum of system is $2\text{kg m/s}$ throughout
3. The momentum of system is $10\text{kg m/s}$
4. The loss of KE of system is $\left(\frac{49}{3}\right)J$

Q. A metal ball of mass $2\text{kg}$ moving with speed of $36\text{kmph}$ is having a collision with a stationary ball of mass $2\text{kg}$. If after collision, both the balls move together, the loss in kinetic energy due to collision is:

1. $80\text{J}$
2. $40\text{J}$
3. $60\text{J}$
4. $160\text{J}$