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Homework Help: Tarzan vine Conservation of Energy

  1. Oct 8, 2008 #1
    1. The problem statement, all variables and given/known data

    A 17 meter long vine hangs vertically from a tree on one side of a 10 meter wide gorge, as shown in the figure. Tarzan runs up, hoping to grab the vine, swing over the gorge, and drop vertically off the vine to land on the other side

    2. Relevant equations

    PE = mgh
    KE = 1/2mv^2

    3. The attempt at a solution

    Since energy has to be conserved, I tried setting to two equations equal to each other. In other words, the kinetic energy he had as he jumped onto the rope, and the potential energy he has at the top of his swing when he isn't moving.

    I got stuck because I can't find 'h', therefore I can't find 'v'

    Thanks in advance
  2. jcsd
  3. Oct 8, 2008 #2
    use right angle triangle to find hypoteneuse using 17 and 10 as the sides.
    Then calculate the angle (so between the ground and the rope = between side length 10 and the hypoteneuse) using trig.
    You can subtract the length of the hypoteneuse by the length of the rope, then use that length with the calculated angle to get the max height- 'h' reached by using trig.
    Then apply energy conservation.
  4. Oct 8, 2008 #3
    Thanks a bunch.. It worked perfectly
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