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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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