How Do You Solve a Leslie Cube Assignment?

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A Leslie cube with a surface temperature of 97°C requires calculations for maximum spectral intensity, total intensity, and total power emitted by a black surface. The user initially applied the formula lambda=2.9*10^-3/T for maximum wavelength and considered Stefan's Law for total intensity but expressed uncertainty about its simplicity. For total power, they multiplied the total intensity by the area of the four sides. Clarification was provided on the spectral energy density in Planck's equation, emphasizing its role in thermal radiation per unit volume. The discussion highlights the importance of converting Celsius to Kelvin for accurate calculations.
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sorry, this was my question from yesturday, and now my assignment is due tomorrow. anyone have any help for me?


A Leslie cube has a surface temp of 97C. One of its four side faces has an area of 100 cm^2 and is painted black. Calculate:

a) the wavelength at which the spectral intensity (per unit wavelength) is a maximum

b)the total intensity (all wavelengths) of the emitted radiation just outside the surface

C) the total power emitted by the black surface

for a) i used lambda=2.9*10^-3/T (not sure if this is the correct way of doing it)

for b) i wanted to use Stefan's Law but this seems to simple

for c) i multiplied the answer from b) by the area of the four sides.

does any of this sound correct? i seem to be struggling on this topic

also, in Planck's energy density equation, what exactly is the spectral energy density? is it also known as anything else? thanks.
 
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You did the problem wery well,all three points of it... :smile:

The volumic spectral energy density (given by Planck's law) has the significance of the thermal radiation/unit of volume in one domain/interval of frequency chosen equal to unity...

Daniel.
 
One more thing to point a) of the problem.I sincerely hope u converted the Celsius degrees into Kelvin ones... :rolleyes:

Daniel.
 
thanks for your input on this. glad to here i did it correctly, and of course i converted to kelvin, thanks for the heads up though
 
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