Originally Posted By: JBjorgen
I think your model of energy transfer needs some work.

No, I think not. The only thing that matters in this scenario is whether you (the driver) remain stationary or accelerate. If you remain stationary, you don't care how much energy transfer takes place, since none of the energy is being transferred to you.

If the car accelerates suddenly (taking you with it, of course) then some of that energy is being transferred to you.

Not having your brakes on at the time of collision might reduce the damage to your car (some of the energy transfer would go into kinetic energy of velocity of your car rather than being dissipated by crushing the back of the car) but since you (the driver) would also absorb some of that velocity, it would increase the damage to you.

tanstaafl.
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