I am stumped... very hard question:(adsbygoogle = window.adsbygoogle || []).push({});

"A 70.0kg woman does a bungee jump. The length of the bungee cord is 5.00m and it has a spring constant of 122.08 N/m. Assume the gravitational field strength is 9.81 N/kg.

a)What is the maximun distance the bungee cord will stretch and how far will the jumper be below her initial start point?

b)How much is the total mechanical energy of the system?

c)How far will the bungee cord be stretched when the jumper is moving at her maximun speed? What is this point called? <- I think its called the equilibrium point.

d)What is the maximun speed the jumper will atain."

So as you can see this is a very difficult question. Ive taken some stabs at it with no luck. Heres what Ive done so far.. but it might be wrong: I found that the initial speed will begin when cord starts to stretch so after 5m of free fall I found Velocity intial would be 9.9m/s then I started my equations:

Total Energy Mechnical (Emt) = Potential Energy Gravity (-ΔEpg) + Kinetic Energy (ΔEk)

Emt= -ΔEpg + ΔEk

Emt -ΔEpg = Eps (Potential spring Energy)

mgh= 1/2kx² height= x+5 where x is the stretch of the bungee cord

mg(x+5)=1/2kx²

√(2mg(x+5))/x= x

as you can see im going nowhere.... what i got lead to a quadratique equation... I dont know if I need to use one or not

Could some one help me solve this question or atleast get me started.

Thanks for help

Cogon,

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# Homework Help: Physics Bungee Jump Question

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