The Bungee Jumper: Conservation of Energy
Obj: Determine the distance a bungee person falls based on the determined k of a spring
Materials:  spring, bungee person, meter stick, weights

Procedures and Analysis
1.  Set up the apparatus as shown in the diagram to find the spring constant k of a spring.
2.  Avoiding parallax, read and record the position of the spring with the 50 g mass hanger attached.
3.  Hang a 50.0 g mass on the mass holder.  Record the new position.
4.  Repeat Steps 2 and 3 for incremental masses of 50.0 g.
5.  Plot F in Newtons as a function of x (meters).  
Calculate the slope of the line (=spring constant k).
6.  Determine the mass of your bungee person.  Solve the equation for the distance (h) the bungee person will fall before being stopped by the spring. 

mgΔh   =  2kh²                   which simplifies to:                      mg = 2kh

     Now, call over the physics instructor for the next step.

7.  Attach the bungee person to the spring and support the person such that the spring is at the no-load (unstretched) position.  Raise the bungee person to the appropriate height (h).  Consider the body length of the bungee person. 
8. Drop the bungee person. [NOTE: The physics instructor is the sole judge of distance from the table the bungee person falls on the spring.]

Grade: bungee person hits table (a fatality) = 1, within 8-10 cm of table = 3, within 4-7 cm = 4, less than 4 cm = 5

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