Answer :
Friction has to do with this. If you have a smoother surface than another surface, the smoother surface will contain less friction. Friction is an opposing force against a moving object. If there is less opposing force towards a moving object, there is less friction. If you have a smooth road, cars won't break as fast as they would break on bumpy roads, because bumpy roads have more bumps, creating more friction. I hope that helped. :D
