Spring Constant and cord length? * Need explanation*

AI Thread Summary
The discussion revolves around calculating the necessary cord length for a bungee jump using a spring with a known spring constant of 29 N/m and a 200g weight. The user is confused about how to apply the spring constant to determine the length of the cord needed to prevent the jumper from hitting the ground after a 10m drop. They express frustration that the spring constant seems inadequate for their calculations, as the spring stretches beyond the initial measurements when the weight is dropped. The user seeks clarification on the mechanics of bungee jumping to aid in a presentation. Understanding the relationship between spring constant, weight, and drop height is crucial for ensuring a safe jump.
Whitetiger101
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Okay, so hi. I am brand new here at PF and I am signed up to ask this because this site appears to have allot of people who actually care and explain how to answer things.


I have a spring and a 200g weight.
- The unstretched spring is: 0.238m long
- Stretched spring (with 200g weight hanging from it): 0.305m long

I calculated the constant of the spring in Newtons per meter : 29N/m
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
We are suppose to drop "a jumper" a.k.a my 200g weight from a 10m drop.
My prblem is to find the length of string i need in order to have a successful bungee jump and not have a dead "jumper"
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
I don't get the constant, because the constant is just the length of the spring with the weight on it, and the spring stretches more then just 0.305m, speacialy if i drop it from 10m up.
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Please help me.
**Conclusion**
29N/m is (to me) a useless value and have no idea on how to get the length of string so that my "jumper" does not die.


Notes: i tried to make this as clear as possible.

Why i need help: Because i would like to know how bungee jumping works. (presentation in english class, need to understand all of it and not just read stuff on google.)
 
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so sorry about posting this here. I read the homework rule after posting this.

Request delete.
 

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