Collisions and Conservation Laws

The video tutorial explains the conservation of linear momentum and the behavior of kinetic energy in collisions. It distinguishes between elastic and inelastic collisions, providing real-life examples like car crashes and billiards. The tutorial delves into mathematical equations for momentum conservation and discusses completely inelastic collisions where objects stick together. It concludes with an analysis of the center of mass and its constant velocity during collisions.

What happens to the total linear momentum of a system if no external force acts on it?

• It remains constant.

• It decreases.

• It increases.

• It becomes zero.

In an elastic collision, what happens to the total kinetic energy?

• It is converted to potential energy.

• It remains constant.

• It decreases.

• It increases.

What is the main difference between elastic and inelastic collisions in terms of energy?

• Elastic collisions conserve kinetic energy, inelastic do not.

• Inelastic collisions conserve kinetic energy, elastic do not.

• Both conserve kinetic energy.

• Neither conserve kinetic energy.

In the context of collisions, what does the term 'inelastic' imply about energy?

• Energy is gained.

• Energy is lost.

• Energy is unchanged.

• Energy is converted to mass.

What is a characteristic of a completely inelastic collision?

• Momentum is not conserved.

• Objects bounce off each other.

• Objects stick together.

• Kinetic energy is conserved.

Which of the following is an example of an inelastic collision?

• A pendulum swinging.

• A perfectly elastic rubber ball bounce.

• A car crash where the cars stick together.

• Two billiard balls colliding.

In a completely inelastic collision, how does the final velocity of the combined mass compare to the initial velocity of the moving mass?

• It is less.

• It is greater.

• It is zero.

• It is the same.

What happens to kinetic energy in a completely inelastic collision?

• It is partially lost.

• It is converted to potential energy.

• It is completely lost.

• It is fully conserved.

What remains constant in a system of two masses before and after a collision?

• The velocity of each mass.

• The velocity of the center of mass.

• The potential energy of the system.

• The kinetic energy of each mass.

How is the velocity of the center of mass calculated in a two-mass system?

• By dividing the total momentum by the total mass.

• By adding the velocities of the two masses.

• By subtracting the velocity of one mass from the other.

• By multiplying the masses by their velocities.