1. The problem statement, all variables and given/known data A guy is riding a bike down a hill. He feels "lighter" when he accelerates than when he's braking. Why? 3. The attempt at a solution I thought that a higher normal reaction force than weight was responsible for feeling "light". But this can't be right. Is it something to do with the fact that less friction is acting on him when he's not braking? Thanks I just need a really *basic* answer because the physics we're doing at the moment is just very basic.