Chemistry behind airbag deployment. How to demonstrate?

[demode]

Hey there everyone!

For my chemistry class, I had to write a feature article about the chemistry behind airbags (pretty fascinating stuff), and now my teacher has dropped the bomb that we must do a presentation that explains what we studied..

I was hoping to do a small (and i mean small) scale demonstration of how airbags work, but I haven't been able to find anything on the internet! If any of you have tried to do a presentation on airbags or might know of any way I can make a good presentation about them, could you please help?

Thanks,

Tom.

 

[jpr0]

You could just do something simple, like taking two eggs, and a plastic bag (and some kind of tupaware container). Blow the plastic bag up, but not so much that it becomes incompressable - you'll have to experiment to see what pressure you need... drop one egg from a height and watch it splatter into the container... drop the second egg onto the airbag, and see that it survives the fall. Both eggs were dropped from the same height and come to rest at approximately the same height, but the difference is that while the hard container brought the first egg to rest over a very small period of time.. the second egg comes to rest much slower (and therefore experience a smaller force upon impact). This is pretty simple and I think captures the general feature of what you want to demonstrate. You can then just show some simple maths working out the average force experienced in these two cases.

By the way, I saw your initial post, about the talk being 8 minutes long. Don't worry about this, 8 minutes is not long atall - probably by the end of the talk you'll wish you had more time.

 

[jpr0]

By the way, when you say "chemistry" of airbags.. you mean the physics of airbags right? In terms of chemistry.. I have no idea... the example I showed you is more to do with physics than chemistry.

oops: I guess it was someone else asking about airbags yesterday.

 

[demode]

Thanks so much for the quick reply jpr0, but yeah I was looking more so at the chemical reactions that actually drive airbags to deploy and whatnot.. Thanks anyways though!

 

[jpr0]

Ah I see..
See this post then:

https://www.physicsforums.com/showthread.php?t=208282&highlight=airbags

The last suggestion by the scary looking monkey man seems quite good.

 

[gravenewworld]

Hey there everyone!

For my chemistry class, I had to write a feature article about the chemistry behind airbags (pretty fascinating stuff), and now my teacher has dropped the bomb that we must do a presentation that explains what we studied..

I was hoping to do a small (and i mean small) scale demonstration of how airbags work, but I haven't been able to find anything on the internet! If any of you have tried to do a presentation on airbags or might know of any way I can make a good presentation about them, could you please help?

Thanks,

Tom.

I doubt you would be able to get your hands on some sodium azide. It is highly toxic, but that is what they use in airbags to deploy them.


The only thing I could think of is if somehow you got your hands on liquid nitrogen. You could fill a balloon with nitrogen, attach it to a test tube and then stick the test tube in the liquid nitrogen. After the balloon deflates you could take the test tube out of the liquid nitrogen and watch the balloon rapidly inflate as the liquid N2 in the test tube heats up into the gas phase.

 

[demode]

Thank you very much for the quick replies! They were very helpful

 

[lightarrow]

I doubt you would be able to get your hands on some sodium azide. It is highly toxic, but that is what they use in airbags to deploy them.


The only thing I could think of is if somehow you got your hands on liquid nitrogen. You could fill a balloon with nitrogen, attach it to a test tube and then stick the test tube in the liquid nitrogen. After the balloon deflates you could take the test tube out of the liquid nitrogen and watch the balloon rapidly inflate as the liquid N2 in the test tube heats up into the gas phase.

Better to take NaN3 with hands than liquid nitrogen...