In many cases when there is friction acting on a body which is rolling without slipping ( for eg : a body rolling down a inclined plane ),
We say, that the work done by the friction is zero as the velocity of point in contact is zero adn it works out.
But the question,I am having is how does friction still comes into play while the relative velocity of the point is zero ? , because as we know when relative velocity is zero , friction shouldn't act. But if the later is only true after friction comes into play then why does it still keep acting after the relative velocity is zero?