Originally Posted by Povl Carstensen
Intuitively, I do not think its the stopping that causes the whip to crack, but the movement before, it is just delayed somewhat. But to crack a whip more, you can pull back a little, which might be in line with the pulling across the body.
well physically energy is transfered by decelerating the prior body part. pulling back has the same effect as stopping.
successive accelerating and decelerating body parts is the foundation of the kinetic chain.