1. Show that the integral over all frequencies of the Planck formula given by U(t) = blah blah (Planck's Formula) gives a result that is of the form (a constant) [Hint: Change variables from f to ] The energy emitted per unit area per unit time, P(T), is proportional to U(T), and thus P(T) is also proportional to as in the Stefanâ€“Boltzmann formula(adsbygoogle = window.adsbygoogle || []).push({});

Don't even know where to start on that one. The hint doesn't help me at all.

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# Homework Help: Need some help on Planck's Formula

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