(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Exercise 1. Two bungee jumpers jump from a bridge. Jumper A is fastened to a bungee cord and holding on to jumper B. The cord has a stiffness k = 80 lb/ft. Find the unstretched length of the cord if the two students just reach the surface of the water at the maximum displacement. If student A lets go of student B at the surface of the water. Is there a problem for student A on the return? The distance between the bridge and water is 120 ft.

2. Relevant equations

T1 + ƩU_{1-2}= T2

U_{1-2}= -WΔy Work of a weight

U_{1-2}= -ksΔs^{2}Work of a Spring Force

3. The attempt at a solution

I solved the first part by using the principle of work and energy, setting T1 and T2 to zero and solving for the s-initial. However, I'm having trouble with the second part. I know that the potential energy from the first part gets transferred to the bungee jumpers kinetic energy in his ascension, and that his final height will be higher than if he didn't let go of the other bungee jumper. Also, I know his final kinetic energy will be zero at his maximum height, and I think the question wants to know if this height will be greater than the height of the bridge over water. Any thoughts?

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# Homework Help: Work/Energy of Two Bungee Jumpers

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