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Satisfying application of physics

  1. Apr 8, 2008 #1
    Today, I completed a lab test in my physics test, and received the highest grade in the class. The goal was to simulate a bungee jump. We had to make the payload, an egg in my case, get as close to the floor as possible without touching. To do this, you get a rubber band, and would then calculate a length of non-elastic string to attach to it. Our goal was within 3cm. The catch? you only get one try. I first got a large rubber band, and suspended it from a fixed arm about 2m off the floor. I measured the displacement of the rubber band, and use a force gauge to measure the force. I used those numbers in F=-kx to find the spring constant. I then found the elastic potential energy with Pe=1/2kx^2. I then took the weight of the egg, in newtons, and calculated the string length with P(elastic)=P(egg) and got .5m. My egg, dropped from the same point that the rubber band was attached to the support, was dropped, and promptly sprang back upon reaching 3cm almost exactly.:approve:

    Just to sum up my work:

    P(elastic)= 1/2kx^2
    2.96= 1/2(13.84).65^2



    Last edited: Apr 8, 2008
  2. jcsd
  3. Apr 8, 2008 #2


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    Very, very good! That's the kind of physics "lab" that I like.

  4. Apr 8, 2008 #3
    thank you very much.

    and BTW, I just met with my college course adviser for the first time today. I am "in", and I'm majoring in physics!!!!
  5. Apr 8, 2008 #4


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    Great job!

    I've had a few similar labs that just *worked* but most of these consist of overcomplicated setups that just manage to work, pure fluke.
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