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Topic Date User

rope jump 2-May-2007 At 11:04:51 AM TonyB

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>you've painted yourself into a corner there. if the rope always stretches
>the same amount, according to your assumptions its always absorbing the
>same amount of energy.

Please read my post again "stretch length is proportional to the length of the rope". That is, a rope twice as long stretches twice as much. The calculator on this page may help you get a better appreciation: http://www.getbeta.com/fall_factor.asp

As people correctly point out, my discussion is just theory. I wouldn't trust it without a real world experiment. 75Kg dummy with load cell, accelerometer and transmitter should do the trick ... and for not much more than the cost of 250m of rope. Alternatively, it might make a nice project for a mechanical engineering student with a uni lending the hardware. A plot a maximum load vs fall height would be most interesting ... it's a wonder it hasn't already been done.