The greater-than-g acceleration of a bungee jumper discussed in a previous article in this journal by Kagan and Kott1 led to many lively discussions among Dutch physics teachers. These inspired me to look for an inexpensive experimental setup, suitable for use in a high school physics class, that can be used to confirm that indeed the acceleration is greater than g. In this paper I describe an exercise to compare the predicted and the measured graphs for the displacement y(t) of the jumper and the force Fb(t) exerted by the bungee on the bridge to which it is fastened. In my apparatus, the “bungee” consists of a light chain and the “jumper” is a small piece of brass. Data collection and the calculation of predicted values were carried out using Coach.2 The analysis reliably leads to the conclusion that the acceleration of the falling jumper does indeed exceed g.

1.
D.
Kagan
and
A.
Kott
, “
The greater-than-g acceleration of a bungee jumper
,”
Phys. Teach.
34
,
368
373
(Sept.
1996
).
2.
Coach is a versatile activity-based environment that makes it possible to: (a) collect data with all kinds of sensors; (b) collect data from video-clips; (c) process these data with advanced mathematical tools; and (d) compare the experimental results with predictions obtained by modeling. Coach also supports Texas Instruments CBLs and Vernier LabPro. Coach is a product of CMA, AMSTEL Institute, Universiteit van Amsterdam. See http://www.cma.science.uva.nl/english, or http://www.harris-educational.com/Probeware.
3.
M. G.
Calkin
and
R. H.
March
, “
The dynamics of a falling chain: I
,”
Am. J. Phys.
57
,
154
157
(
1989
).
4.
The CMA Dual-Range Force Sensor B0362bt. The Vernier Dual-Range Force Sensor DFS-BTA could also be used.
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