Question

Maximum value of static friction:
A. limiting friction
B. rolling friction
C. normal friction
D. coefficient of static friction

Answer 1

Hint: We know that friction is the resistive force which tries to oppose the motion of an object. It is a surface phenomenon and is observed only when the object trying to move is in contact with some surface. Which is to say that friction is a contact force.

Complete answer:
Friction can be classified into three types broadly.
1. Static friction: is the friction experienced when one tries to move a body which is at rest , such that there is no friction between the body and the surface.
2. Kinetic friction: is the friction experienced when the object is in relative motion to the surface.
3. Normal friction: is a perpendicular component of the contact force. It is equal and opposite in direction to the gravitational force experienced by a body. Clearly, C is not the answer.
The limiting friction and the rolling friction are a special type of static friction and kinetic friction c respectively.
 Rolling friction is the friction experienced by a moving circular body along the surface. As rolling friction is due to movement, option B is not the answer.
 Limiting friction is the friction observed when the body experiences an external force greater than the friction such that the body begins to move. And is known as the maximum value of static friction.

So, the correct answer is “Option A”.

Note:
Friction is a small quantity that acts in the opposite direction to the force. Static friction is the force responsible for an object to be at rest, whereas the kinetic friction is the force that resists the motion of a moving body. Also normal friction is observed in both the cases.