Grandma has a new car that uses rocket brakes to slow it down. The car has a mass of 850 kg. She starts out by moving forward with a speed of 12.8 m/s. She then applies the rocket brakes, but as the car comes to a stop she forgets to take her foot off the brake pedal and the rocket continues to apply its force. She ends up moving backwards with a speed of 9.32 m/s. The total time the brakes were firing was 6.74 seconds. (a) Find the change in momentum of the car. (b) Using the formula for impulse, calculate how much force the rocket brake was applying to the car on average, including the direction?

Grandma has a new car that uses rocket brakes to slow it down. The car has a mass of 850 kg. She starts out by moving forward with a speed of 12.8 m/s. She then applies the rocket brakes, but as the car comes to a stop she forgets to take her foot off the brake pedal and the rocket continues to apply its force. She ends up moving backwards with a speed of 9.32 m/s. The total time the brakes were firing was 6.74 seconds. (a) Find the change in momentum of the car. (b) Using the formula for impulse, calculate how much force the rocket brake was applying to the car on average, including the direction?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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