Finding specific heat of an object graphically

AI Thread Summary
To find the specific heat of an object graphically, the heat gained by sample B must equal the heat lost by sample A, leading to the equation Qb = Qa. The specific heat formula Q = mcΔt is applied, where Δt represents the temperature change. There is confusion regarding the correct temperature change to use, with suggestions that it should be from 100 to 40 degrees instead of 100 to 60 degrees. Clarification is needed on the correct interpretation of Δt in the context of the problem. Understanding these relationships is crucial for accurately calculating the specific heat.
armolinasf
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Homework Statement



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.




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
 

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armolinasf said:
The heat gained by object b must equal the total heat of object a.

I think it is better to replace the underlined by 'heat lost by'.
 
armolinasf said:
but Q=mcΔt ==> c=Q/mΔt would Δt then just be the total change from 100 to 60 degrees?

I think that you mean that \DeltaT is the change from 100 to 40, i.e. 60deg because we are considering A.
 
armolinasf said:
So Qb=Qa=Q/mb*mb, mb=mass of object b.

Can the poster explain what the above mean?
 
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