Impulse for a car when it drives in a circle

AI Thread Summary
The discussion revolves around calculating the impulse experienced by a car during a turn and a collision. For the turn, the impulse is determined to be zero since the car's velocity remains constant, despite the change in direction. The impulse during the collision with the tree is calculated at 7420 kg·m/s, resulting in an average force of 21200 N over 350 ms. A participant notes the importance of considering the radius of the turn, which can be derived from the given tangential speed and time taken to complete the quarter circle. Understanding these dynamics is crucial for accurately solving the physics problems presented.
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Homework Statement


A 1400kg car is driving at a constant velocity, 5.3 m/s. It turns 90 degrees in 4.6 seconds. And then it slams into a tree and it takes 350 ms to stop the car.
What is the impulse on the car (a) due to the turn? (b)Due to the collision with the tree?
What is the magnitude of the average force that acts on the car (c)during the turn? (d)During the collision with the tree?
What is the angle between the average force in (c) and the positive x direction?


Homework Equations


Impulse = j = p2-p1 = mv2-mv1
F = ma


The Attempt at a Solution


a) 0. Since the velocity does not change, and the mass is constant, there is no change between p1 and p2.
b) j = (1400)(5.3) - (1400)(0) = 7420
c) F = 0/(4.6) = 0
d) F = (7420)/(0.350) = 21200
e) I have absolutely no clue on how to even start this one.


Thanks in advance for any help!
 
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Well for the parts where the car is making the turn, there's a force that you might be forgetting about. Basically, during the turn, the car is in Uniform Circular Motion for a quarter of a circle.
 
If I am not given the radius of the turn, how can I still use the uniform circular motion formula?
 
You're given the time it took to make a quarter of a circle and you're given the tangential speed during the turn. There's a relationship between those that will give you the radius.
 
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