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Homework Help: Water fall question

  1. Dec 13, 2003 #1
    a waterfall is 30 m high and 10000 kg of water flow over it every second
    A) calculate the potential energy
    PE = mgh
    got 2.94E6 joules

    B) calculate the power delevered by the water of all the potential energy is converted to work

    F = mA
    F= 10000 * 9.80
    f = 98000

    w = Fm
    w 98000 * 10000
    w = 980 MJ mega joules

    C)If all the power were converted to electricity, how many 100watt light bulbs could be lit

    not even sure on how to approach this
    [?]
     
  2. jcsd
  3. Dec 13, 2003 #2
    B is WRONG Look at the physicsl dimensions when u multiply force by mass is it Energy
     
  4. Dec 13, 2003 #3
    Look the energy mgh which u calulated is per second
    which is power itself

    with this energy u can lit mgh/100 bulbs

    hope u will get now
     
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