Question

Whenever the surfaces in contact tend to move or move with respect to each

other, the force of friction comes into play

(a) only if the objects are solid.

(b) only if one of the two objects is liquid

(c) only if one of the two objects is gaseous.

(d) irrespective of whether the objects are solid, liquid or gaseous.​

Answer 1

Option (a) only if the objects are solid . is right answer .