Answer:
It results from microscopic bumps and ridges.
It causes a change in motion.
It is the opposite to the direction of the motion.
It is parallel to the surfaces that rub together.
Explanation:
Friction force acts when there is tendency of relative motion between two surfaces. It always opposes the motion i.e. it always acts in the opposite direction to the applied force parallel to the surfaces which rub together.
The magnitude of the friction depends on the roughness and surface area of the two bodies in contact. It causes change in motion as it slows down the object in motion.
The roughness is due to the microscopic bumps and ridges structure of the surface. These bumps and ridges interlock with each other and resist the motion.
Thus, the correct statements which describe friction are:
- It results from microscopic bumps and ridges.
- It causes a change in motion.
- It is the opposite to the direction of the motion.
- It is parallel to the surfaces that rub together.
