T-boned in intersection, airbags didn't deploy

[mdm]

Originally Posted by Tectoniic

Please tell me you're trolling. If not, basic physics would like a word with you.

EDIT: In case we are trying to say the same thing but something was mistyped:
60 MPH Car -> + <-60 MPH Car =/= 60 MPH Car -> + Wall

60 MPH Car -> + <-60 MPH Car = 120 MPH Car -> + Wall

He's right, and your EDIT 2 sort of goes in the correct direction. When two cars front-collide a6 60 + 60 mph you have two crumple zones, figuratively speaking each taking care of its own 60 mph. When hitting a wall at 60 mph, you have only one crumple zone "taking care" of one 60 mph. Same thing. Some stationary objects may dissipate energy, but in case of a solid concrete wall, or a thick tree, it's completely negligible.

[mdm]

Originally Posted by Tcoat

Side bags inflate and stay inflated for a much longer than front bags since they are designed to take a lighter but possible longer or larger number of impacts

On the other hand, they inflate/deploy much faster, because, when t-boned, there is very little space (and time) between the side window/B-pillar and your head. In frontal collisions you are pretty far from the dash/steering wheel, and crumple zones increase the time between impact on the sensor and the time when airbags are needed.

Originally Posted by Tcoat

they are only actually inflated for a microsecond.

Only figuratively, I think. Airbag deployment/deflation times are measured in milliseconds or tens of milliseconds

[murdoc]

Originally Posted by Tectoniic

P
60 MPH Car -> + <-60 MPH Car =/= 60 MPH Car -> + Wall

60 MPH Car -> + <-60 MPH Car = 120 MPH Car -> + Stationary car

FTFY

[EAGLE5]

Here's how I think about it:
If an object is traveling at speed x, then it will hit with power x.
If two objects are traveling at speed x and hit each other head on, they will both experience hits of power x from each other.
If an object at speed x hits an immovable object, the immovable object will experience a hit of power x, but it will hit back at the moving object with power x. If it does not, it will have to move.

In other words, walls push back.

[Tectoniic]

Originally Posted by mdm

He's right, and your EDIT 2 sort of goes in the correct direction. When two cars front-collide a6 60 + 60 mph you have two crumple zones, figuratively speaking each taking care of its own 60 mph. When hitting a wall at 60 mph, you have only one crumple zone "taking care" of one 60 mph. Same thing. Some stationary objects may dissipate energy, but in case of a solid concrete wall, or a thick tree, it's completely negligible.

Yea I'm going to admit I'm wrong and edit my wording to be a bit less hostile :P

In terms of the frame of reference I am correct that with 2 60 MPH head on cars the frame of reference sees it as a 120 to stationary and for a 60 into the wall the frame of reference sees it as 60 to stationary.

It comes down to the 2 cars sharing the impact equally vs the wall putting the full impact on the car(in ideal physics land)

[Tcoat]

Originally Posted by NoCones

Common misconception. Two equivalent cars hitting each other head on at the same speed is not materially different from one car hitting a stationary, immovable object at that same speed.

Yes. If two cars of equivalent mass it is the same. So hitting another Twin head on that applies. Hitting a transport or 59 Buick is the equal to hitting a brick wall moving at you at speed not a stationary one. You will not be splitting the energy if you tangle with a vehicle heavier than you. now I am sure I can get the calculations for the split per pound from the crash test dudes at work if I try hard enough.

[Sarlacc]

Originally Posted by Tcoat

Yes. If two cars of equivalent mass it is the same. So hitting another Twin head on that applies. Hitting a transport or 59 Buick is the equal to hitting a brick wall moving at you at speed not a stationary one. You will not be splitting the energy if you tangle with a vehicle heavier than you. now I am sure I can get the calculations for the split per pound from the crash test dudes at work if I try hard enough.

Exactly.
After a head on collision with a bowling ball and a basket ball, the basket ball will be moving backwards and will thus have experienced a much larger delta-v.

If you want to survive a collision, drive one of these; filled to the brim with cement.

[NoCones]

Originally Posted by Tectoniic

Deleting because i was confusing overall frame of reference speed with damage done to the car.


EDIT 2: I feel like im going to have to keep adding qualifiers that in this case the wall is an immovable object that also takes no damage and 100% of the damage is done to the car. In a real life scenario some damage and movement to the wall occurs but have fun calculating that

fundamentally, in either case, the car goes from x speed to zero really quick...the rest is fairly immaterial

[Tcoat]

Originally Posted by NoCones

fundamentally, in either case, the car goes from x speed to zero really quick...the rest is fairly immaterial

The moral of the story is that if you are going to have a head on try to pick the smallest and lightest opponent you can.

[soulreapersteve]

ft86club...

Where we argue MT vs AT, which color is the best, N/A vs FI... and math shit.

[dalli]

Originally Posted by murdoc

The front airbags wont deploy for side impacts most of the time.

i got t-boned which spun my car multiple times and caved in the dashboard toward my legs from side.

air bags from wheel and dash board deployed but had no air in them

'94 toyota tercel

[murdoc]

Originally Posted by dalli

i got t-boned which spun my car multiple times and caved in the dashboard toward my legs from side.

air bags from wheel and dash board deployed but had no air in them

'94 toyota tercel

Yeah, they're only inflated for a fraction of a second, so they aren't useful in secondary impacts.

[dalli]

Originally Posted by murdoc

Yeah, they're only inflated for a fraction of a second, so they aren't useful in secondary impacts.

im sure it had air for a bit of a second, all i can remember. i was blacked out for that fraction of a second

[murdoc]

Originally Posted by dalli

im sure it had air for a bit of a second, all i can remember. i was blacked out for that fraction of a second

Well good thing you made it out alive.

I was in an accident in a tercel where I was rear ended by a Crown Victoria.

It felt like I was in a football getting punted.