A boxer stops a punch with his head. To approximate the force of the blow, treat the opponent's glove, hand, and forearm as aparticle of mass 1.68 kg moving with aninitial velocity of 21.5 m/s.
a) Estimate the force exerted on the head if the hand moves forward 8.0 cm whiledelivering the blow and then coming to rest.
b) Estimate the force exerted on the head if the head is deliberately moved back during the punch so that the hand moves forward 16 cm while decelerating.