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Kathy,
Car collisions are actually quite complicated but think about this - the car driving at 60mph has a lot of kinetic energy that has to be converted into something else in a collision - more often than not to its passengers. A stationary car has no kinetic energy to lose. In a collision between a fast moving car and one that is stationary energy will be transferred and I'd prefer to be in neither car. Given the choice though, I'd rather not be in the one that goes from 60-mph to zero in a very short space of time to the one that goes backwards at a much slower velocity.
If cars acted like billiard balls then it doesn't matter what car you're in, but they don't.
In other words, Rob's advice is right.
I do have a little bit of a background in physics but admit I haven't thought this through thoroughly, but the car moving fast is the one that has most to lose.
Rob - one thing I'd worry about with your advice - does turning off the engine disable the airbags? I think it does and would prefer them to work. If you're in a stationary car and get shunted from in front, your head is going to hit the steering wheel unless the bags are active.
Tom
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It is not my expectation that we are dealing with suicidal Honda CRX's. Their goal appears to be to scare people off the road. If you are stopped or nearly stopped they are left with one choice... they have to move in another direction.
If faced with a wrong way driver I suggest to worry less about what may or may not be behind you and pay very close attention to the approaching wrong way driver who is presenting himself as an imminent threat.
My daughter's car is an '82 MBZ. No airbags. Lots of steel. So I suggest she turn off her engine and brace. I would expect the wrong way fool to move but if he is simply too stupid you can't predict what will happen. I'd be disappointed to find out that airbags only work with an engine on. Anybody know?
Assume the best and ask questions.
Punaweb moderator
Assume the best and ask questions.
Punaweb moderator
Maybe move off the road first Rob ? Give the maniacs some room to change their minds.
Part two is to tell your Daughter to NOT grip the wheel rather hold her arms out loosely in front of her. Proven to reduce injury in both crash test dummys and stuntmen.
aloha,
pog
Thanks TomK,
makes sense. Yes, I can tell they're complicated! One thing I read (quickly) is that if the cars bounce off each other (rebound) there is more force/kinetic energy than if they stick and crumple. I also read that force and time are inversely proportional, so that something that extends the TIME in which a crash unfolds reduces force. That is what airbags do, as do the crumple zones. In addition, when cars stick together the momentum shifts to them traveling together, which is less than when they rebound off each other, and crumple zones facilitate that. That is the gleanings of my five minutes physics research.
My remark about the stationary car came from an accident I was in many years ago. We were broadsided while entering an intersection going slowly from a full stop, hit by a pickup going 55 mph. The truck driver was fine, but our driver was injured a lot. On reflection though, probably because we were hit from the side which has less protection.
Rob, I speak of all this with the conviction that your daughter will not end up in this situation, or I wouldn't talk about it in such clinical terms. Personally I would not have the nerve to face an oncoming driver playing chicken and HOPE he makes a rational choice or -- figures out in time that the other car is not going anywhere.
So I looked up the airbags question online. It says airbags need electricity to activate. So while the engine need not be running, the ignition must be on or they will not work!
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There's been advice about what to do if you see idiots racing towards you which is all fine and good and a little bit about the physics about what might happen if the worst comes to the worst. It doesn't matter very much when you have morons driving you off the road and usually there's not enough time to react anyway let alone use the advice on this thread.
So how about some ideas on a solution? Making H130 a divided highway will work but we all know that won't happen soon. Educating young drivers is fine but I doubt it will have any effect on the people who deliberately put other drivers at risk. The only solution I can think of is having more cops on patrol. My own experience is during the rush hour drivers are more considerate than at other times (this is relative, many aren't) because we're all trying to get to the same place. The really dangerous drivers are out at other times but I know some are also out there on the commute.
So what do we do? Any ideas? I'm for more cops but with the economy I doubt that can happen.
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Kathy - we should all drive in billiard balls, it would make the physics so much easier!
PS. As I said it's not simple - given a collision between a stationary car and a 20-ton truck moving at 60-mph I'd rather be in the truck!
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"So what defensive techniques would people suggest when faced with an idiot playing Chicken on a road at night?"-Rob's question...
Puna's no complex city -
I would recommend several Gents with cell phones and heavy duty rigs, trucks, hummers, rovers or what have you go canvas the area for this scum. When some-one finds him, ye-all take it from there. All converge on him and contact police or handle it old school. If old School, make sure you've an old beater rig for the sac and a wrecker to clean up the field
BTW... the opposite holds true with relatively similar weight class vehicles, the faster vehicle in a collision will suffer less damage and so will it's occupants if only considering the vehicles colliding. The vehicle that is not in motion will be pulverized and so will its occupants. This all has to do with inertia.
A vehicle that is not in motion has less inertia than a vehicle in motion which has more inertia.
E ho'a'o no i pau kuhihewa.
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We can only hope he trys this chicken game with a big old tow truck one morning and looses big time. In the meantime its better to be "chicken" than dead any day of the week. Def. pull to the right as far as possible in control and reduce your speed. Remember to never jerk the wheel, that could cause you to go out of control or roll the car especially if you over correct getting back onto the pavement.
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