ive been working on this problem and i have a solution too, but it doenst work. the reason i know that it doesnt work is because we have to submit our answers to a computer system that tells us if our answer is right or wrong. please help?(adsbygoogle = window.adsbygoogle || []).push({});

A blackened, solid copper sphere of radius 5.70 cm hangs in a vacuum in an enclosure whose walls have a temperature of 21.0°C. If the sphere is initially at 0.0°C, find the rate at which its temperature changes, assuming that heat is transferred by radiation only. Also assume that the sphere has an emissivity of 1.

here is what i did:

Pnet = dQ/dt = mc dT/dt

one two skip a few and...

dT/dt = [3eσ(T^4 – T0^4)]/rρc

its right...but it doenst work!

please help?

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# Homework Help: Find the rate at which its temperature changes

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