Question

During an elastic collision between two bodies, which of the following statements are correct?

• A. I, II, and III
• B. I and II only
• C. II and III only
• D. I and III only

Hint:

In elastic collisions, focus on the conservation of kinetic energy and momentum. If these are conserved, the collision is elastic.

Answer 1

The Correct Option is D

In an elastic collision, the two primary conditions are: - Kinetic Energy is conserved: The total kinetic energy before and after the collision remains the same. - Linear Momentum is conserved: The total momentum of the system before and after the collision remains unchanged, provided no external forces act on the system. Let’s evaluate each statement: 1. The initial kinetic energy is equal to the final kinetic energy of the system: - This is true for elastic collisions, as both kinetic energy and momentum are conserved. 2. The linear momentum is conserved: - This is also true in an elastic collision. Linear momentum is conserved unless external forces are involved. 3. The kinetic energy during the collision (the collision time) is not conserved: - This is true in the sense that the total energy remains constant, but energy can be transferred to other forms like heat or sound during the collision process. However, this is not a contradiction because we are concerned with the total system energy, which remains conserved in an ideal elastic collision. Thus, statements I and III are correct. Therefore, the correct option is (4) I and III only.