Grandma has a new car that uses rocket brakes to slow it down. The car has a mass of850 kg. She starts out by moving forward with a speed of 12.8 m/s. She then appliesthe rocket brakes, but as the car comes to a stop she forgets to take her foot off thebrake pedal and the rocket continues to apply its force. She ends up movingbackwards with a speed of 9.32 m/s. The total time the brakes were firing was 6.74seconds. (a) Find the change in momentum of the car. (b) Using the formula forimpulse, calculate how much force the rocket brake was applying to the car onaverage, including the direction?

Mass of car (m) = 850 kg Initial speed (u) = 12.8 m/s (in forward direction) Final speed (v) = 9.32…

Answered: Grandma has a new car that uses rocket…

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter10: Systems Of Particles And Conservation Of Momentum

Section: Chapter Questions

Problem 41PQ: There is a compressed spring between two laboratory carts of masses m1 = 105 g and m2 = 212 g....

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