# Q & A: Bungee cord accident

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Most recent answer: 04/15/2009
Q:
My husband got hit in the face with a bungee cord last summer. The bungee cord was a regular household bungee cord. . .about 5 feet when it was not stretched out, and about 8 feet when it was fully stretched. While it was fully stretched it became dislodged and the hook sailed straight into his face (yep-- knocked out some teeth). I've just always wondered-- how many pounds of force hit him?
- Heather (age 37)
Vancouver, WA
A:
Apparently, quite a number of pounds considering the number of teeth knocked out.  Given the information you have supplied it is not possible to calculate the exact answer.  One has to know the elastic strength of the cord, i.e., how many pounds does it take to stretch the cord to a certain length.
Let this be a lesson to others who read this post:  springs in general can store up lots of energy.  This energy can be released in a short amount of time with catastrophic results.

LeeH

I'd suggest calibrating the energy stored in the bungee cord by seeing how much weight it holds when stretched to 8 feet. Then you could figure out how fast the end was flying, using energy conservation, and get about how strong the impact was. But you worry that the same thing could happen again. Mike W.

(published on 04/15/2009)