Question

According to the definition of oblique collision in the paragraph, which of the following collisions cannot be oblique?
A. Collision between two point masses.
B. Collision between two rings of same radius,
C. Collision between two rings of different radius.
D. Collision between a particle and a ring of finite radius.

Answer 1

Hint: Look for the definitions of oblique collision and head-on collision. Point out the necessary condition for a collision to be oblique or head-on. From the given options check which option does not satisfy the condition of oblique collision.

Complete step-by-step answer:
First, let’s understand the collision before the oblique collision.
When two or more objects interact with each other with a very high force for a small duration of time, then it is termed as a collision. These objects need not be in physical contact with each other. The force with which these bodies interact is called an impulsive force and its duration is very small. This impulse force is responsible for a change in a moment of the body during the collision.
When the line joining the center of masses of two bodies is not parallel to the direction of their velocities then a collision is said to be an oblique collision and if it is parallel then it is called unidirectional collision or head-on collision.
To have an oblique collision bodies must have some dimensions. Since point masses do have many dimensions, their collision is always a head-on collision.
Answer is A. Collision between two point masses.

Note: Note that the collision could occur even without physical contact of bodies. A collision may be elastic or inelastic. A collision is said to be elastic if there is no loss of kinetic energy, otherwise, it is called an inelastic collision. The momentum of the colliding system is always conserved.