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Homework Help: Heat Energy Question

  1. Dec 10, 2007 #1
    1. The problem statement, all variables and given/known data
    Much of the energy of falling water in a waterfall is converted into heat.

    If all the mechanical energy is converted into heat that stays in the water, how much of a rise in temperature occurs in a 100 m waterfall?


    2. Relevant equations
    q=mc(Tf-Ti)
    Q=mc Delta T
    Delta T = |Tf-Ti|


    3. The attempt at a solution

    i have no idea where to start or what equation to use all i see is the 100m can some one please lead me in the correct direction with the correct formula to use.
     
  2. jcsd
  3. Dec 10, 2007 #2
    potential energy = mgh

    This is the energy available to be converted to heat.
     
  4. Dec 10, 2007 #3
    ok so P.E.=MGH

    P.E. = M(9.8)(100)

    is this correct there are still 2 unknows
     
  5. Dec 10, 2007 #4
    If all the energy is converted into heat then P.E. = Q

    Set them equal and solve for delta T.
     
  6. Dec 10, 2007 #5
    ok so the equation would look like this

    M(9.8)(100) = mc Delta T

    but i still need to know the Mass and MC am i overlooking something??
     
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