Question

Answer the following question:

A. Why is sliding friction less than static friction for the same surface?

B. A book of mass 1 kg is at rest on the table. Maximum value of static friction is 5N and sliding friction is 4N.
Now, Answer:

i. If we apply a force of 4.5N will the body move from rest?
ii. If we apply a force of 6N will the body move from rest?
[5 MARKS]

Answer 1

Part A : 2 Marks
Part B : 3 Marks

A. Sliding friction is always less than static friction because two sliding objects find less time to get interlocked against each other’s irregularities of surfaces as a result of which they experience less friction.

B.
i) No, minimum force required to move the body from rest is 5N
ii) Yes, Force is greater than 5N, so it will start moving.