Radiation Rate of 0.1m Cube Metal at 200C

AI Thread Summary
To calculate the radiation rate of a 0.1m cube of metal with an emissivity of 0.75 at 200°C, the formula H=AeσT^4 is used, where σ is the Stefan-Boltzmann constant. The area of one face of the cube is 0.01 m², and since a cube has six faces, the total area is 0.06 m². Converting 200°C to Kelvin gives 473K, and substituting these values into the formula results in a radiation rate of 128W, correcting the initial miscalculation of 21.28W. Proper unit conversion and consideration of the cube's total surface area are crucial for accurate results.
Kyle North
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Homework Statement


At what rate does a 0.1m cube of metal with emissivity e=0.75 radiate energy if it is at a temperature of 200C?

Homework Equations



H=AeσT^4, σ=5.67 x10^-8

The Attempt at a Solution


I found the area of the cute to be A=(0.1m)^2=0.01m, and the turned 200C into 473K, but when I type them all in I get 21.28W and the answer is 128W?
 
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How many faces does a cube have?
 
6.. thanks!
 
Also, (0.1 m)2 = 0.01 m2 Don't forget to square the units.
 

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