# Spring Constant – Bungee Jumping

**1. The problem statement, all variables and given/known data**

A person with a mass of 65 kg goes bungee jumping. At the lowest point, he is located 30 m below his starting point. If, at the equilibrium point, the bungee cord measures 15m, what is its spring constant?

**2. Relevant equations**

F = k*x

Ep = (1/2)(k)(x^2)

**3. The attempt at a solution**

At the bottom, all the gravitational potential energy is converted to elastic potential energy.

mgh = (1/2)(k)(x^2)

(60 kg)(9.8 m/s^2)(30 m) = (1/2)(k)(30^2)

k = 39.2 N/m

I am not sure if this is correct, why did they give the equilibrium information? What does that mean?

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