Determine speed of car from result of impact?

AI Thread Summary
Calculating the speed of a car from an impact is complex and not very accurate without professional tools. The discussion highlights that while basic physics principles like velocity, friction, and mass can be considered, idealized setups may not yield reliable results. The individual involved in the accident is curious about the speed due to airbag deployment, suspecting it was over 25 mph. However, participants advise against DIY accident reconstruction and recommend consulting a specialist for accurate analysis. Ultimately, understanding the specifics of the collision requires professional expertise.
doggonemess
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Greetings,

It's been quite a while since I had to do anything with velocity, friction, mass, and practically any physics over simple calculations. My car was hit yesterday while parked. There were no injuries, and it still drives just fine. The collision was hard enough to deploy the other car's airbag.

I don't need to know the answer for legal reasons, it's all being taken care of by insurance. But out of curiosity, is there a way to calculate the velocity of the car from the data that I have?

I can tell from how offset my car is from straight how much it moved. I know the masses of both vehicles, as well as the road surface where my car was sitting for the friction of the tires.

Can someone noodle this one out? I'd love to know.

Jamie
 
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doggonemess said:
is there a way to calculate the velocity of the car from the data that I have?
No. Accident reconstruction is a very tricky business. Of course you can do some idealised setup where you can input what you know, but it will not be very accurate.
 
Orodruin said:
No. Accident reconstruction is a very tricky business. Of course you can do some idealised setup where you can input what you know, but it will not be very accurate.

I'm happy with making some assumptions and getting a ballpark figure. I suspect they were going faster than 25 mph due to the airbag deployment. I'm wondering if they were going much faster than that.
 
doggonemess said:
Greetings,

It's been quite a while since I had to do anything with velocity, friction, mass, and practically any physics over simple calculations. My car was hit yesterday while parked. There were no injuries, and it still drives just fine. The collision was hard enough to deploy the other car's airbag.

I don't need to know the answer for legal reasons, it's all being taken care of by insurance. But out of curiosity, is there a way to calculate the velocity of the car from the data that I have?

I can tell from how offset my car is from straight how much it moved. I know the masses of both vehicles, as well as the road surface where my car was sitting for the friction of the tires.

Can someone noodle this one out? I'd love to know.

Jamie
As already pointed out, we do not help with accident analysis and reconstruction here. Please consider hiring a specialist to help you with this.
 

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