A space probe is traveling in outer space with a momentum that has a magnitude of 7.84 x 107 kg·m/s. A retrorocket is fired to slow down the probe. It applies a force to the probe that has a magnitude of 1.29 x 106 N and a direction opposite to the probe's motion. It fires for a period of 9.65 s. Determine the momentum of the probe after the retrorocket ceases to fire.

Answer 1

mv = 7.84*10^7
acceleration from the force is
a = F/m = -1.29*10^6/m
so, v after force is

7.84*10^7/m - (1.29*10^6/m)(9.65)
= 6.6*10^7/m

so the final momentum is 6.6*10^7 kg-m/s

sorry about using m for mass as well as meters.