Question

If you throw a ball horizontally while standing on roller skates, you roll backward with a momentum that matches that of the ball. Will you roll backward if you go through the motions of throwing the ball, but instead hold on to it?

Answer 1

here, linear momentum will conserve.

initial linear momentum is zero because both ball as well as person are in rest. so, as the ball moves forward in the

hand of person, persion will also go backward with same momentum to make to total momentum zero.but as the ball comes to rest in the hand of persion, persion will also comes to rest abuptly.

so, overall conclusion - yes, we go backward if we go through the motion of throwing ball but holding the ball in our hand. :)