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I am a beginner and I have a problem regarding Planck's Quantum Theory
The following is one of the postulate of Planck's Quantum Theory
1) The energy of each quantum is directly proportional to frequency of radiation.
Q.) What is the sense of the word "frequency" here, despite the fact that Planck's Quantum theory contradicts wave nature of Electromagnetic radiations? (Since, Frequency is defined for waves).