Question

A space probe is traveling in outer space with a momentum that has a magnitude of 4.99 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 1.87 x 106 N and a direction opposite to the probe's motion. It fires for a period of 11.1 s. Determine the momentum of the probe after the retrorocket ceases to fire.



Not sure what I am doing wrong. Here is my work:

4.99*10^-7 => Implusion
1.87*10^6 => Average Force
11.1 => Time

((4.99x10^(-7))/(1.87x10^(6))(11.1)) = 0.000000000002961979

But this is not the answer. Please help!

Answer 1

change in momentum = Force * time = impulse = -1.87*11.1*10^6 = -2.08*10^7

4.99*10^7 - 2.08*10^7 = 2.91*10^7 kg m/s

Answer 2

Thank you so much!