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- What does 'per unit frequency' refer to? 2 answers
What is the meaning of power radiated by a black body per unit frequency?
If you have a black body with a frequency filter around it set to 530nm and you calculate the energy radiated in 1 second
you will get a definite (not a differential) value. So where does "per unit frequency" come from? What is its physical meaning?
There is a physical anamoly in my argument as, suppose, at 530 nm we get 5 watt energy, so at 530.01 nm the power will approximately be the same 5 watt, and similarly for 530.001nm.
But I still don't get the flaw in my argument (even though I get that the result is wrong). What is it that I am missing?