A100-g bullet is fired from a rifle having a barrel 0.600 m long. choose the origin to be at the location where the bullet begins to move. then the force (in newtons) exerted by the expanding gas on the bullet is 15 000 1 10 000x 2 25 000x 2 , where x is in meters. (a) determine the work done by the gas on the bullet as the bullet travels the length of the barrel. (b) what if? if the barrel is 1.00 m long, how much work is done, and (c) how does this value compare with the work calculated in part (a)?