Calculating the Minimum Safe Drop Height for a Bungee Jumper

[shawn123]

Homework Statement

Our lab was to predict the distance a bungee jumper will fall before coming to rest.
I already found the spring constant
When we have the spring constant we had to find the minimum safe drop height for a bungee jumper before being stopped by the spring. The following conditions apply:
a. the bottom of the spring will be 1.6 m above the ground
b. a string of length Ls will be attached to the spring
c. the bungee jumper will be attached to the string
d. the bungee jumper will have length Lj
e. the bungee jumper will have mass m
We are not provided with these values, but have a make an equation in which we can plug numbers in so we can get the jumper as close as to the ground without killing themselves. The spring is fastened at one end, on the other end there is a string attached and to the end of the string is a bungee jumper. A small mass will represent the jumper. Can anyone help me. Thanks.

Homework Equations

F=-kx
Mgh=.5mv^2
F=ma

The Attempt at a Solution

I used mechanical energy, but don’t really know where to go.

 

[WhoWee]

You may need to adjust the length of the jumper to account for the point of connection?