Question

Does friction increase as the smoothness increases between two areas?

Answer 1

Friction is increased with increase in smoothness as the friction coefficient between the two surfaces decrease, so resistance by friction decrease.

But when we make Surfaces ultra-smooth, inter molecular forces starts to act between the two surfaces as they come very close to each other due to which, it becomes harder to make them slide on each other. In other words, friction between them is increased but actually it is due to inter molecular forces.