Heat capacity and temperature problem

AI Thread Summary
The discussion revolves around a problem involving the heat capacity of a metal heated at a constant power. The participant initially struggles with the relationship between power, heat transfer, and temperature change. Clarification is provided that power is defined as the rate of change of heat (P = dQ/dt) and that heat capacity is related to temperature change (C = dQ/dT). After further analysis, the participant confirms the correct relationship, concluding that P = Ck is accurate. The exchange highlights the importance of understanding derivatives in thermodynamic equations.
Krushnaraj Pandya
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Homework Statement


A piece of metal is heated by supplying a constant power P. The temperature of the metal starts varying as T=kt. The heat capacity of the metal as a function of temperature is?

Homework Equations


Q=CdT

The Attempt at a Solution


From Q=CdT, dT is k, since P is Q/t, I plugged this into the equation but the answer is way off. Can someone explain what I'm missing?
 
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Consider how you've defined power: P = Q/t. Is that correct? Generally we think of power as the rate of energy delivered or consumed per unit time.
 
You are missing what you missed in your other post. Power is rate of change and involves a derivative not a ratio. Here, ##P=dQ/dt##. You need to consider that ##C=dQ/dT## and relate that to ##P= dQ/dt##.
 
kuruman said:
You are missing what you missed in your other post. Power is rate of change and involves a derivative not a ratio. Here, ##P=dQ/dt##. You need to consider that ##C=dQ/dT## and relate that to ##P= dQ/dt##.
oh ok, so P=dQ/dt and dQ=CdT, therefore Pdt=CdT, P=CdT/dt therefore P=Ck, is this correct?
 
That looks correct.
 
kuruman said:
That looks correct.
I got it, thank you very much :D
 
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