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solarcat

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## Homework Statement

A person is bungee jumping from the top of a cliff with height H. The un-stretched length of the bungee rope is L. The person comes to a stop just before hitting the ground. The length of the cord is equal to H(amax-g)/(amax+g), where amax is the maximum acceleration upward right before the person hits the ground. Show this equation is physically reasonable by evaluating it when amax = g and amax = infinity.

## Homework Equations

Conservation of energy

## The Attempt at a Solution

amax = g

L = H(g-g)/(g+g) = 0

This means that the cord starts stretching right as the person jumps.

amax = infinity

L = (infinity -g)/(infinity+g)*H = H

If the length of the cord is equal to H, the cord never starts stretching.

If the cord never starts stretching, then the jumper is always in free-fall, and the acceleration is equal to g. Then shouldn't the results be the other way around?