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Homework Help: Finding specific heat of an object graphically

  1. Oct 21, 2011 #1
    1. The problem statement, all variables and given/known data

    Samples A and B are at different initial temperatures when they are placed in a thermally isolated container and allowed to come to thermal equilibrium. Figure a gives their temperatures T versus time t. Sample A has a mass of 5.2 kg; sample B has a mass of 1.6 kg. Figure b is a general plot about the material of sample B. It shows the temperature change T that the material undergoes when energy is transferred to it as heat Q. The change T is plotted versus the energy Q per unit mass of the material.

    3. The attempt at a solution

    The heat gained by object b must equal the total heat of object a. So Qb=Qa=Q/mb*mb, mb=mass of object b.

    but Q=mcΔt ==> c=Q/mΔt would Δt then just be the total change from 100 to 60 degrees?

    this would give me 25600/(5.2*60)=82.05 which is incorrect. Where Am I going wrong?

    Thanks for the help

    Attached Files:

  2. jcsd
  3. Oct 21, 2011 #2
    I think it is better to replace the underlined by 'heat lost by'.
  4. Oct 21, 2011 #3
    I think that you mean that [itex]\Delta[/itex]T is the change from 100 to 40, i.e. 60deg because we are considering A.
  5. Oct 21, 2011 #4
    Can the poster explain what the above mean?
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