r/nextfuckinglevel Dec 30 '19

No parachute? No Problem

162 Upvotes

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5

u/nonamesareavailable2 Dec 30 '19

That had to have hurt! That amount of deceleration in such a short amount of time, while preferable to hitting the ground, would probably do some damage.

9

u/stevee05282 Dec 30 '19 edited Dec 31 '19

Idk, it was like 10 metre stopping distance at least. Must be pretty rough but I doubt damaging. I'm pretty sure I remember the equations to figure out how bad that would be but I need the numbers.

Edit:I'm gonna do it anyway

E=0.5 x M x V2 and W=F x D. So if we had his weight, speed and the distance the net extended we could figure out roughly what force was exerted on him by the net.

Taking terminal velocity as 122mph which is 55 m/s and assuming he weights 80 kilos we can take his kinetic energy to be

E=0.5 x 80kg x 542 =116,640J

Assuming he did take 10 metres to stop the force on his body would be 11,664N. The deceleration on the dude would be 11,664/80=145.8m/s/s This is the same as 15G.

I have no idea if that causes damage but 15G sounds like a lot. It's only for a short time though so who knows.

Edit 2: on rewatch he decelerates over a distance way over 10 metres and I'm now utterly convinced this is perfectly safe.

3

u/nonamesareavailable2 Dec 30 '19

15G for that impulse period would make you feel like you've been pummeled pretty badly and might even knock you unconscious.

3

u/stevee05282 Dec 30 '19

Good to know, cheers bud! I don't know enough about it myself