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Photoelectric effect and Aluminum

  1. Mar 30, 2007 #1
    A 0.4 kilogram sample of Aluminum at 115 degrees Celsius is put into a container containing 0.5 kilograms of water at 15 degrees Celsius. Neglecting the small amount of energy absorbed by the container and knowing that the specific heat of Aluminum is 900 kJ/kg*C, and the specific heat of the water is 4186 kJ/kg*C answer the following question.

    Compared to the heat liberated by the aluminum, the heat absorbed by the water is

    greater. wrong


    the same.

    is it smaller or the same?
    Last edited: Mar 30, 2007
  2. jcsd
  3. Mar 30, 2007 #2
    what are the units of heat? what then is heat?
  4. Mar 30, 2007 #3
    heat is...energy, thermal energy, or a change in temperature, measured in Joules
  5. Mar 30, 2007 #4
    and what things have you learnt about energy?
  6. Mar 31, 2007 #5
    It is exactly the same with the following example. You pour a cup of water into a bucket. Then asked: compare the mass gained by the bucket and the mass lost by the cup. The answer now so simple.
  7. Apr 1, 2007 #6
    It's the same since they already told you to ignore the heat absorbed by the container.
  8. Apr 1, 2007 #7
    Hmmm... why is this a question about the photoelectric effect? It seems to be just a thermodynamics question, perhaps there's a trick somewhere?
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