Say whether the following statements are true/false : (a) Kinetic friction depends on velocity of the body. (b) Static friction is independent of area of contract. (c) Kinetic friction is directly proportional to normal reaction.
Answers
Answer:
true
false
false
here you go!
(a) Kinetic friction depends on velocity of the body.
true, Kinetic friction depends on velocity of the body. Friction force depends on the nature of the materials in contact and their coatings for both static and kinetic (moving) conditions and is independent of velocity of body.
(b) Static friction is independent of area of contract.
false, Friction is independent of the area of contact. The reason behind this is that the actual area of contact on an atomic scale is a fraction of the total surface area. Friction depends only on the nature of surfaces in contact and the weight of the body.
(c) Kinetic friction is directly proportional to normal reaction.
false, Kinetic friction is defined as the friction force which acts on a moving body and it acts opposite to the direction of motion of anybody. Here the normal reaction of the body is equal to the weight of the body. so the kinetic friction is directly proportional to the normal reaction of the body.