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Homework Help: Water equivalent of calorimeter

  1. Feb 26, 2015 #1
    1. The problem statement, all variables and given/known data
    The water equivalent in kg, of a calorimeter having a mass of 0.3 kg and a specific heat of 0.2 is

    2. Relevant equations

    3. The attempt at a solution
    I wanted to set cmT = cmT for the water and calorimeter, but I don't know what the equilibrium temperature is.
    So what do I do?
  2. jcsd
  3. Feb 26, 2015 #2


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    That's good. Simplify what you set up, and you're in business.
  4. Feb 26, 2015 #3
    Can I cancel out the T's then?
    In that case, I would have c1m1 = c2m2
    (0.2)(0.3) = (4.186)m2
    m2 = 0.014 kg

    But the answer says it's 0.06 kg
  5. Feb 27, 2015 #4


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    You have met one of many sloppily stated questions you'll run into in your life. "Specific heat" has been conflated with "Specific gravity." Since water has a specific gravity of "One," the author of the question has chosen "One" as the specific heat for water as well. In kcal/kg, yes, but there is no specification of units in the problem statement.

    Your understanding is correct, and your application of that understanding is correct.
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