Blackbody radiation and stefans constant

AI Thread Summary
The rate of energy radiation per unit area of a blackbody at 260K can be calculated using Stefan-Boltzmann's law, which states that the energy radiated is proportional to the fourth power of the temperature. The calculation involves multiplying Stefan's constant (5.67x10^-8 W/m^2K^4) by the temperature in Kelvin raised to the fourth power, resulting in approximately 259.105 W/m^2. Some participants express confusion regarding the phrase "per unit area," questioning if it implies a different calculation is needed. However, the consensus is that the straightforward application of the formula suffices for this problem. Understanding the definition of Stefan-Boltzmann's constant clarifies its use in these calculations.
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What is the rate of energy radiation per unit area of a blackbody at a temperature of 260K ?

Where's the tricky part in this question?

Surely the answer to this question can't be just

stefans constant * T^4

ie. 5.67x10^-8 * 260^4 = 259.105 W/m^2
 
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Not every problem is tricky. The hard work was done to derive the constant. If you had been asked to that, it would be a whole different thing.
 
That's the question. Nothing else was asked.

What confuses me is how it says ...per unit area...in the question. So I'm thinking maybe they want some other number, I'm not sure
 
What's the definition of Stefan-Boltzmann's constant...?

Daniel.
 
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