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Homework Help: Question about the Conservation of Energy

  1. Dec 10, 2009 #1
    If a cart rolled down a ramp 5 meters high and flew off a a table at 3 meters high, what would its velocity be?

    please let me know where i go wrong, i was using the law of conservation of energy

    mgh1=mgh2+1/2mv2
    mg(h1-h2)=1/2mv2
    v=square root of 2g(h1-h2)

    where h1=5 and h2=3

    i plugged in numbers for the variables and i can't seem to get it to work out. is the equation i came up with correct?
    edit: i was thinking that it should come out to the square root of 2gh. would that be right though? can i consider the release height to be the "0" height here?
     
    Last edited: Dec 10, 2009
  2. jcsd
  3. Dec 10, 2009 #2

    rock.freak667

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    Homework Helper

    Yes your equation is correct, though since the ramp is 5m high and then the table is 3m high, shouldn't h1=8m?
     
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