Question

if another body c is contact with b
​

Answer 1

Answer:

Generally with friction the contact force, F

c

=μN

but here F

c

=N, so there in no friction force between the block. Otherwise they may not slip on each other.

Hope it helps you.. :)

Answer 2

Answer:

1: the force of the friction between the body is zero.

2: the bodies may be rough but thay don't slip on each other