Impulse Momentum: Comparing Forces

AI Thread Summary
A car traveling at 60.0 m/s crashes into a wall, and the average force acting on a 70 kg passenger who is not wearing a seatbelt is calculated to be 1.2 million Newtons when brought to rest in 3.5 milliseconds. In contrast, the average force exerted by an airbag, which brings the passenger to rest over 40 milliseconds, is significantly lower at 105,000 Newtons. The calculations for both scenarios are confirmed to be accurate based on the momentum change formula. The discussion highlights the drastic difference in forces experienced by a passenger during a collision with and without an airbag. Understanding these forces is crucial for assessing safety measures in vehicles.
marisa29
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1. 2) A car is moving at 60.0 m/s and crashes into a wall. The messenger is not wearing his seat belt.
a. What is the average force acting on the passenger of 70 kg if he is brought to rest by a collision with the windshield and dashboard that lasts 3.5 ms.
b. Compare this value of the average force with the average force exerted by an air bag that bring the passenger to rest in 40 ms.



2. delta(p)=Force*delta time
Fave= delta p/ delta t


The Attempt at a Solution



a) Momentum of the person
70 kg * 60 m/s = 4200 kg*m/s
F ave= 4200/.0035 sec= 1.2*10^ 6 N

B) 4200/.040 sec= 10.5*10^4 N
 
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So what is your question? You need to start being more specific what you need help with.

Your math looks fine and I would think that's the right answer if your equation are correct.
 
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