I am to derive the incorrect Rayleigh-Jeans formula from the correct Planck formula to show why plank's constant does not appear in the Rayleigh-Jeans formula. I should also recall the Stefen-Boltmann Law(adsbygoogle = window.adsbygoogle || []).push({});

here's what I have but I'm stuck...

Rayleigh-Jeans formula: [tex]u(\lambda)=\frac{8 \pi k T }{\lambda^{4}}[/tex]

Planks formula: [tex]u(\lambda)=\frac{8 \pi k T }{\lambda^{4}}\frac{hc/ \lambda}{e^{hc/ \lambda K T} - 1}[/tex]

so I am thinking I am somehow supposed to get: [tex]\frac{hc/ \lambda}{e^{hc/ \lambda K T} - 1} = 1[/tex] but I dont know how to even begin. any ideas?

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# Homework Help: Rayleigh jeans formula

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