Units of plancks law in terms of wavelength

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SUMMARY

The discussion centers on the dimensional analysis of Planck's law, specifically the units derived from the equation \(\frac{h c^2}{\lambda^5}\). The correct dimensional units for this expression are confirmed to be J/(m³·s), as stated by Wikipedia. The confusion arises from the interpretation of the wavelength term, \(\lambda\), which is raised to the fifth power in the denominator, leading to the discrepancy in unit representation. This clarification is essential for accurate application in quantum physics and thermodynamics.

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Hypatio
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The dimensional term in Planck's law (after getting rid of steradians) is

\frac{h c^2}{\lambda^5}[\itex]Which seems to yield units of J*m/s. However, Wikipedia suggests that the units are J/(m<sup>3</sup>*s). If wikipedia is right, how do you get that answer?
 
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How did you get J*m/s? There is a length to the 5th power in the denominator.

(the closing tag is [/itex])
 

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