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Everyone on earth

  1. May 28, 2004 #1
    what would happen if EVERYONE (humans) jumped at the same time and landed at the same time?....would there be a giant earthquake or what?
  2. jcsd
  3. May 28, 2004 #2


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    As a rough estimate, let's say every human has a mass of 100 kg and can jump 1 meter high. Both of those numbers are higher than the average person attains, but not by a whole lot. The energy expended by a person is then mgz = 100 kg x 10 m/s^2 x 1 m, approximately. So each person expends about a thousand joules with one good leap. If there are six billion people jumping, you get 6 trillion joules of energy.

    I went to this website:


    to convert to tons of explosive, and it told me that the total energy would be 1,434 tons of explosive, so call it a kiloton. I believe that a 10-kiloton nuclear bomb is a very modest one by today's standards. If you explode a very modest bomb near the ground surface in the middle of Nevada, does it even shake the buildings in Las Vegas enough that anyone would notice? The jumping-humans scenario would only be one-tenth as energetic. If you are worried about some global catastrophe, you need not fear.
    Last edited: May 28, 2004
  4. May 30, 2004 #3
    I say we should do the experiment! But, as Janitor wrote, everyone jumping up and down at once wouldn't do much. So let's see if we can't improve the odds a bit. Let's have everyone jump up in sequence, say based on their lattitude, at t = 1:30:00 PM Greenwhich Time, July 1 - Latitude/60. This will start a wave that begins at the north pole at noon and takes three minutes to propogate to the south pole. I'm not a geologist, so I'm not sure if the timing is right, but that works out to a propagation speed of 88 miles per hour through the center of the earth. With a little luck, the waves will reinforce constructively.

    Everybody willing to join in?
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