Momentum, K.E. Relation

Q. A molecule in a gas container hits the wall with speed v at an angle θ with the normal and rebounds with the same speed as shown in Figure. Which of the following statement is/are true?

1. The momentum of the system is conserved in the collision.
2. The momentum of the molecule before collision with the wall is equal to the momentum of the molecule after collision.
3. The collision is elastic.
4. The collision is inelastic.

Q.

A bullet having some initial velocity $v_B$ hits a ballistic pendulum of mass $m_B$ and lodges in it. When the bullet hits the pendulum it swings up from the equilibrium position and rises up to height $h$ as shown in figure.

Choose correct option.

1. Kinetic energy of bullet before collision will be same as potential energy of (bullet+pendulum) at height $h$.
2. Kinetic energy of (bullet+pendulum) after collision will be same as potential energy of (bullet+pendulum) at height $h$.
3. Collision between bullet and pendulum is completely elastic.
4. None of these

Q.

A particle of mass m moving in the x direction with speed 2v is hit by another particle of mass 2m moving in the y direction with speed v. If the collision is perfectly inelastic, the percentage loss in the energy during the collision is close to:

1. 44 %

2. 56 %

3. 50 %

4. 33

Q. A bullet of mass $20\text{g}$ and moving with $600\text{m/s}$ collides with a block of mass $4\text{kg}$ hanging with the string. What is velocity of bullet when it comes out of block, if block rises to height $0.2\text{m}$ after collision?
(Take $g=10{\text{m/s}}^2$)

1. $200\text{m/s}$
2. $150\text{m/s}$
3. $400\text{m/s}$
4. $300\text{m/s}$

Q. A particle of mass $1\text{kg}$ suffers one - dimensional elastic collision with an unknown mass at rest. It rebounds directly backward by losing $64\%$ of its initial kinetic energy. The unknown mass $\left(\text{in kg}\right)$ is

Q.

A molecule in a gas container hits a horizontal wall with speed 200 m s^–1 and angle 30° with the normal, and rebounds with the same speed. Is momentum conserved in the collision? Is the collision elastic or inelastic?

Q. A body of mass 60 kg moving with velocity 2 m/s collides with a body of mass 40 kg moving with velocity 4m/s. Calculate the loss of energy assuming perfectly inelastic collision?

Q. How conservation pf momentum follows law of conservation of energy.And write full form of complete equation