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Injury of two animals falling

  1. Oct 11, 2008 #1
    If a turtle and beetle fall from the same height, which would sustain more injury? Assume that both the turtle and beetle are geometrically similar. The amount of force of which the creatures reach the ground would be the measured parameter, right? So, including air resistance in the equation, how would one determine how much force the creatures reach the ground? F = ma, i.e. the amount of injury would depend on the creatures' mass alone (assuming that biological issues are neglected)? What if the creatures have reached their terminal velocity before reaching the ground, i.e. they are not accelerated; F = m(0) = 0?
  2. jcsd
  3. Oct 11, 2008 #2


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    The injury comes when they hit the ground. At that point they will decelerate, and the amount of deceleration indicates the amount of force the ground exerts on them. I don't know how to calculate the deceleration for turtles or beetles. I also don't know if a turtle and beetle are by their biology equally injurable. Terminal velocity is given approximately by Stokes Law.
  4. Oct 11, 2008 #3


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    Not quite sure how to explain why I think beetle is safer. It seems the beetle's innards are held in place better, and wouldn't move very much relative to the rest of the beetle. For heavier animals, there is a lot more relative movement and deformation of organs.

    At least it seems that way to me.
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