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Direct Loading of Dyneema Slings 14-Apr-2010 At 2:20:53 PM Hendo

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I think the point trying to be put across is that the effect of fall distance on force is small compared to the effect of the damping factors associated with having a deformable floppy body, deforming the harness etc. Eg a big change in fall height can be negated by a small change in the rigidity of your body. In theory this is likely to be true but I haven't tested it in any scientific way and couldn't put exact or really even close ball park figures on it for real situations.

A simple rough demonstration would be to get a set of scales, a stiff ball (perhaps a ball bearing or maybe a golf ball) and a non-stiff ball (like a superball) and bounce them onto the scales at different heights and see what peak values you get. You should find the stiff ball generates high forces even from low heights. If you have a suitably less stiff ball you can drop it from much higher and still have same peak force.

I remember doing this a long time ago with a basket ball dropped from roughly body height and being surprised to get a peak force roughly about my weight.

Hooke's law is ok for many non stretchy materials eg. steel.