Small rockets are used to make tiny adjustments in the speeds of satellites. One such rocket has a thrust of 35 N. If it is fired to change the velocity of a 71500 kg spacecraft by 64 cm/s, how long should it be fired?

1 answer

Thrust x time, also known as "impulse", must equal the momentum change desired. In your case the momentum change required is
7.15*10^4 kg * 0.64 m/s = 4.58*10^4 kg m/s
Set this equal to 35 Newtons * T and solve for T. It will be in seconds