Find rate of temperature change using heat capacity, density and area

AI Thread Summary
The discussion focuses on calculating the rate of temperature change using heat capacity, density, and area. The initial calculations yield a rate of heat change (dQ/dt) of 746593.71 W and a mass of approximately 27689.783 kg based on the given density and volume. The main challenge is relating the change in heat to temperature change, with suggestions to use the equation Q = mcΔT and consider the time interval Δt. It is emphasized that dividing the heat equation by Δt can help connect dQ/dt to the temperature change rate. The final goal is to determine the change in temperature using the derived relationships.
JoeyBob
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Homework Statement
see attached
Relevant Equations
dQ/dt=Ae*5.67E-8*T^4
So first I found rate of heat change using the above equation, with T=883K, e=1, SA= 6*l^2=21.66

Now dQ/dt=746593.71 W

Now I am not sure entirely what to do next. They give density so I likely have to get the mass from that, M=pV,=1.9^3*4037=27689.783 kg.

My issue is that I don't know how to relate change in heat to h=change in temperature.

I could try Q=mc(change in T). But I have change in Q, not Q. Not sure how I would integrate dQ/dT either...

Answer is -0.04121 btw.
 

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What is the definition of specific heat capacity? Might be relevant...
 
JoeyBob said:
I could try Q=mc(change in T). But I have change in Q, not Q.
You have Q = mcΔT. Let Δt be the time interval corresponding to the change in temperature ΔT. Think about the equation that you get by dividing both sides of Q = mcΔT by Δt. For small Δt, how does the left side relate to dQ/dt?
 
TSny said:
You have Q = mcΔT. Let Δt be the time interval corresponding to the change in temperature ΔT. Think about the equation that you get by dividing both sides of Q = mcΔT by Δt. For small Δt, how does the left side relate to dQ/dt?

So I can find dQ/dt using dQ/dt=A*5.67E-8*T^4

I can find m using m=pV

And I know Q=mc(change in T)

But dQ/dt isn't Q. Or can I just put it in the equation anyways and solve for change in T and it will work?
 
$$\frac{dQ}{dt}=mc\frac{dT}{dt}$$
 
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