Question

A ball rolling on the ground stops on its own after some time. Why?
A. The ball is stopped by an external force.
B. The force of friction acts against the motion of the ball.
C. The ball moves only for a set period of time
D. None of the above

Answer 1

Hint:Friction is the resistance of one object moving relative to another in response to motion. Like gravity or electromagnetism, it is not a fundamental force. Instead, scientists claim it is the product of the electric attraction between two interacting surfaces between charged particles. Friction is needed in all types of motions. We can walk properly because of friction. Friction is applied on car brakes.

Complete answer:
Friction is the force that resists the relative motion of rigid objects, layers of air, and components of material sliding against each other. Several forms of friction exist: Dry friction is a force which in contact opposes the relative lateral movement of two solid surfaces. Dry friction between non-moving surfaces and kinetic friction between moving surfaces is subdivided into static friction.

The friction between layers of a viscous fluid moving relative to each other is defined by fluid friction. Lubricated friction is an example of fluid friction in which two rigid surfaces are separated by a lubricant fluid. Skin friction is a part of drag, the force that opposes a fluid's motion over a body's surface. Internal friction is the force that resists displacement between the components that make up a rigid object when deformation occurs.

When we roll a ball on the ground, the electrons on the surface of the ground in the atoms press against the electrons that hit the ground in the atoms on the surface of our ball. A rolling ball ceases when its motion is resisted by the surface on which it moves. A rolling ball, due to friction, ceases.

Hence, option B is correct.

Note:The force of friction works between the ball's surface and the surface of the earth as the ball bounces on the ground. The irregularities between the two surfaces are trapped against each other, thereby stopping the ball from travelling forward until an external force pushes it.