Spring Constant [Please Check Work]

AI Thread Summary
The discussion revolves around calculating the spring constant of a bungee cord used by a 98 kg jumper who oscillates after jumping. The initial calculation yielded a spring constant of 44.732 N/m, but the poster doubts its accuracy, noting that they did not factor in the jumper reaching the lowest point three times within 9.3 seconds. They realize the period of oscillation may not be correctly represented by 9.3 seconds. The need for incorporating gravity into the calculations is also highlighted. Clarification on the correct period and approach to the problem is sought.
BuGzlToOnl
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Homework Statement


A bungee jumper, whose mass is 98 kg, jumps from a tall building. After reaching his lowest point, he continues to oscillate up and down, reaching the low point two more times in 9.3 s. Ignoring air resistance and assuming that the bungee cord is an ideal spring, determine its spring constant.

Homework Equations


\omega=\sqrt{k/m}

\omega=2\pi/T

The Attempt at a Solution



2\pi/9.3s = \sqrt{k/98kg}

k = 44.732N/m [?]

I rewrote the equations so I can try to obtain.

The answer I got 44.732N/m, but that seems way to low, can anyone verify if its right/wrong and where I went wrong

EDIT: Well I think I'm wrong because I never used the fact that he reached the lowest point 3 times and didn't incorporate gravity. Not sure on how to approach this so any help would be appreciated.
 
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Hi BuGzlToOnl,

BuGzlToOnl said:

Homework Statement


A bungee jumper, whose mass is 98 kg, jumps from a tall building. After reaching his lowest point, he continues to oscillate up and down, reaching the low point two more times in 9.3 s. Ignoring air resistance and assuming that the bungee cord is an ideal spring, determine its spring constant.


Homework Equations


\omega=\sqrt{k/m}

\omega=2\pi/T



The Attempt at a Solution



2\pi/9.3s = \sqrt{k/98kg}

I don't believe the period is 9.3 seconds. Do you see what it needs to be?
 
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