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Some Weird Questions On Aerodynamics

  1. Aug 15, 2012 #1
    Sorry for this weird thread.

    Say that you throw a perfectly round 10 lb stone rock using a machine with constant force and distance of propulsion.

    Can a 10 lb ("average") human head,with full hair about 2 inches long, be thrown -using the same machine - just as far as the 10 lb rock?

    How about a 10 lb human head with a shaved head?

    Again, I apologize for these weird questions. It's just that I was arguing with someone and this topic came up. My position was that a human head is not really aerodynamically efficient, and will fall far short behind the perfectly round 10 lb rock.
  2. jcsd
  3. Aug 15, 2012 #2


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    That is weird.
    For a minute there I thought you meant a 10 pound human head of size 2 inches, in which case there might not be on PF an expert in shrunken heads but you never know.

    If your machine throws your bowling ball rock 10 feet, then it would necessarily throw the human head 10 feet also

    As the distance of throw increases, the velocity of ejection also increases, and so does the air drag. I would again assume the human head would have more drag then a bowling ball, so the bowling ball wins the toss contest and gets the gold.

    The hairy head would get bronze and the bald one silver.

    Then again, are these pointy heads shaped like a bullet in which case all bets are off.
  4. Aug 16, 2012 #3


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    on the other hand the dimples on a golf ball make it go further. So it's not totally inconceivable that the "head" might go further at high enough velocities (and perhaps with a bit of spin).

    There is only one way to find out and halloween is coming soon :-)
  5. Aug 17, 2012 #4
    That is true :D
  6. Aug 17, 2012 #5


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    Are you planning to storm a castle soon or something?

    Just in general, a human head will use more drag than an equivalently sized spherical object so you would likely need more throwing power. Put a bigger counterweight on that trebuchet!
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