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Hitting Water at Terminal Velocity

  1. May 28, 2003 #1


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    What would happen if you hit a body of water( say an ocean) at the terminal velocity of a person of avg proportions without any special clothing on..just like a jumpsuit? (how would it change for Feet first/head first/belly flop/at an angle etc?)
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  3. May 28, 2003 #2


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    Terminal velocity is about 200mph. Hitting ANYTHING at 200mph is basically instadeath.
  4. May 28, 2003 #3


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    Then again, there are stories of people who have survived such falls...
  5. May 28, 2003 #4


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    Headfirst/Feetfirst, about 200mph. Belly flop; about 90.
  6. May 28, 2003 #5
    At less than terminal velocity, you might want to consider hitting concrete instead if you can. It compresses. Water on the other hand, has a very low compressability at such speeds. There is a trick people do for diving very high heights. Drop a fairly heavy object before you to break the surface tension. But ya, at terminal velocity your probably going to be killed no matter what you hit.
  7. May 28, 2003 #6
    A human will die at hitting the water at a minimum of 60 mph. Water has a very strong surface tension, trust me I've hit it at about 40 mph, it hurts like hell.
  8. May 28, 2003 #7


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    It hurts at 5MPH. But maybe I'm not that tough.
  9. May 29, 2003 #8
    It's nowt to do with the surface tension and all to do with inertia - basically shifting the water out of the way fast enough - 'added mass' is the term when shifting liquids. If you can minimise the amount to be shifted, and ensure that it is struck by a non-vital organ (i.e hands and not head) then you increase your survival chances. That's what a high diver would do.

    I doubt whether you'd survive a 200 mph impact under any circumstances.
  10. May 29, 2003 #9
    Re: Re: Hitting Water at Terminal Velocity

    More like 250 mph and 140 mph.
  11. May 29, 2003 #10
    Yes, when they hit 30-50 ft of snow or in similar circumstances.

    Basicly serious inguries start at a=20g and practically no one survives beyong 30g acceleration.

    One can easily calculate required braking distance s=v2/2a for any velocity v and maximal braking acceleration a. For 200 mph and a=25g you get minimal braking distance to be about 17 m (~50 ft).
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