Which of the following statements regarding laws governing the friction between dry surfaces are correct?

A The friction force is directly proportional to the normal force.
B The friction force is dependent on the materials of the contact surfaces.
C The friction force is independent of the area of contact.
D all of the mentioned

Correct Answer: all of the mentioned

Following are the laws of solid friction : 1. The force of friction is directly proportional to the normal load between the surfaces. 2. The force of friction is independent of the area of the contact surface for a given normal load. 3. The force of friction depends upon the material of which the contact surfaces are made. 4. The force of friction is independent of the velocity of sliding of one body relative to the other body.
Bissoy MCQ
#Machine Kinematics #Coefficient of Friction

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