Heat capacity and temperature problem

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
5 replies · 1K views
Krushnaraj Pandya
Gold Member
Messages
697
Reaction score
73

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?
 
Physics news on Phys.org
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?
 
kuruman said:
That looks correct.
I got it, thank you very much :D