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by mlhpdx·3y ago·view on hn ↗
Physics. Increasing speed (rapidly) increases kinetic (impact) energy. Braking reduces it. Slow down to 35 and if the truck hits your car it will be damaged. Try to race ahead and hit the truck at 80 mph and you will die (or worse).

Obviously things aren’t so clear cut but your argument is nonsense.

2 comments
This thread. >.<

The kinetic energy in an accident between two vehicles is their relative speed, not their absolute speed.

If you are doing 80 mph and hit a truck doing 70 mph, there's not 80 mph * vehicle mass worth of impact energy.

And that's not even breaking things into directional vectors and calculating the fraction of velocity in the direction of impact.

Vectors and stuff. Maybe throw a tensor or two in there? Or the Lagranian and Hamiltonian and get it right. Given the choice of two small metal boxes in a field of nearby similarly massive and much more massive objects with positive and negative relative velocities, you really choose the one with the greater velocity as “safer”? Right after you bounce off that truck your next hit may well be one going in the other direction. Or something concrete. Seems pretty clear cut to me (and is backed up by decades and millions of deaths over the last 100 years).
Please think about how long a semi truck is. If you are near the back, obviously it is safer to slow down. If you are near the front, it might well save your life to accelerate.

Edit: I’m sure a bit of calculus on the physics of it would reveal the location on the truck where acceleration was more likely to prevent a crash.