[EIDXA] Physics question

[David Christ]

I can't answer the question as asked, but this I know - 

Static (Low elongation) ropes are not recommended by the UIAA (Union Internationale des Associations d'Alpinisme) for catching falls.  Dynamic ropes are rated for this kind of use.  Dynamic ropes have stretch which slows the fall before the stop.  However UIAA certified ropes do not meet OSHA standards.

Good climbing harnesses/lanyards contain devices to decelerate a falling body.  This is to prevent high forces on either the rope or the person.

Experts will correct me, but it seems that if the rope has zero stretch (never true) that means the falling body is stopped instantly which means an infinite G force.  Like hitting a rock.

David K0LUM

On Jun 21, 2013, at 11:28 AM, Jason Joens wrote:

> Grr!  My phone seems to like to send blank emails. Sorry about that!
> 
> 
> 
> Ok.  I weigh about 200 pounds.  So if I'm hanging on the end of a rope, I'm
> putting about 200 pounds of force on that rope.  But what happens if I fall
> 3 feet, and the rope stops my fall?  How much force did I just put on that
> rope?  Assuming a static rope with negligible stretch.
> 
> 
> 
> Jason
> 
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