Question

A solid sphere rolls without slipping on a rough horizontal floor, moving with a speed It makes an elastic collision with a smooth vertical wall. After impact:
(This question has multiple correct options)
A) It will move with a speed initially
B) Its motion will be rolling without slipping
C) Its motion will be rolling without slipping initially and its rotational motion will stop momentarily at some instant
E) Its motion will be rolling without slipping only after some time.

Answer 1

Hint: In order to find the solution of the given question, we need to have a clear concept of collision and its types. Also, we need to have an idea of the collision between the objects. We need to know about the impact as well as to find the correct answer of the given question.

Complete answer:
First of all let us find the concept of collision.
Collision: When two or more bodies violently exert forces on each other for a short period of time, we define it as collision.
Now, we know that after collision the force of friction will be acting in the opposite direction of the motion. Also, after the collision, the body will be in its initial angular motion, which will be in clockwise direction. Due to friction, there will be a linear retardation which will ultimately reduce the speed. Due to this, there will be an angular acceleration which will be decreasing until it reaches zero. After this the angular acceleration would be in anticlockwise direction, which will lead it to roll until the slipping begins. When slipping will be there, then after some time the effect of the force will be reduced to zero.
Now, as we see the options, we can conclude that the body will move with initial velocity, its velocity will be rolling without slipping initially and the rotational motion will stop momentarily. Also the motion will be rolling without slipping only after some time.

Hence, option A, C and D are correct choices of the given question.

Note: We say a body is rolling when the rotation and translation motion of a body is combined. If an object can slide over a surface it is said to possess slipping motion. A body can roll with or without slipping.