Help w/ a physics problem
 

I need help with this quick problem. For some reason I can't figure it out.

Automobile Airbags: The human body can survive a negative acceleration trauma incident (sudden stop) if the magnitude of the acceleration is less than 250 m/s^2

If you are in an automobile accident with an initial speed of 108 km/h (30 m/s) and are stopped by an airbag that inflates from the dashboard, over what distance must the airbag stop you for you to survive the crash?

Thanks

Re: Help w/ a physics problem
 

[ QUOTE ]
I need help with this quick problem. For some reason I can't figure it out.

Automobile Airbags: The human body can survive a negative acceleration trauma incident (sudden stop) if the magnitude of the acceleration is less than 250 m/s^2

If you are in an automobile accident with an initial speed of 108 km/h (30 m/s) and are stopped by an airbag that inflates from the dashboard, over what distance must the airbag stop you for you to survive the crash?

Thanks

[/ QUOTE ]

vf^2 - vi^2 = 2ad
a = 250 m/s^2
vf = 0
vi = 30 m/s

so d = (900)/(2*250) = 9/5 m

Re: Help w/ a physics problem
 

Can you explain to me how this works. I don't see how there is enough information in the question to have an answer. How do we know how fast the airbag is moving/accelerating back at you?

Re: Help w/ a physics problem
 

Thank you!

Re: Help w/ a physics problem
 

[ QUOTE ]
How do we know how fast the airbag is moving/accelerating back at you?

[/ QUOTE ]

Although the problem doesnt say it, it is reasonable to assume that the airbag is fully inflated before your body hits it.

Re: Help w/ a physics problem
 

Bradyams, I'm glad you got your question answered.

If there are any moderators reading this, though, I think you need to have a separate topic for "Science & Math" and another topic heading for "Religion & Philosophy." I'm afraid that anyone who has a science-math interest might be turned off by the overwhelming majority of posts that aren't related to this subject and then when anyone has a question like this, the questioner won't find as many people reading it who are interested and knowledable enough to help. But if there were two seperate topics, they could both be thriving. Just my opinion, I could be wrong.

Re: Help w/ a physics problem
 

[ QUOTE ]
Bradyams, I'm glad you got your question answered.

If there are any moderators reading this, though, I think you need to have a separate topic for "Science & Math" and another topic heading for "Religion & Philosophy." I'm afraid that anyone who has a science-math interest might be turned off by the overwhelming majority of posts that aren't related to this subject and then when anyone has a question like this, the questioner won't find as many people reading it who are interested and knowledable enough to help. But if there were two seperate topics, they could both be thriving. Just my opinion, I could be wrong.

[/ QUOTE ]

Agreed. The religion discussions are like freshman year of college and totally dominate this thread.

Re: Help w/ a physics problem
 

No, the airbag doesn't even have to deploy for you to survive. There's a bigger chance, based on evidence I would assume, that you will survive if the airbag deploys. And those numbers about force are just estimations. You can be killed by much less,and survive much worse. It has alot to do with what your body runs into.
Shooby