Spring constant of a bungee cord from oscillation period

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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


[tex]\omega[/tex]=[tex]\sqrt{k/m}[/tex]

[tex]\omega[/tex]=2[tex]\pi[/tex]/T

The Attempt at a Solution



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

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


[tex]\omega[/tex]=[tex]\sqrt{k/m}[/tex]

[tex]\omega[/tex]=2[tex]\pi[/tex]/T



The Attempt at a Solution



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

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