A doubt regarding Planck's quantum theory

Question

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).

Possible duplicates: https://physics.stackexchange.com/q/427859/ , https://physics.stackexchange.com/q/30804/, https://physics.stackexchange.com/q/303458/ — jacob1729, Jun 14 '19 at 16:55
There is no Planck's quantum theory. Planck is of of the many brilliant scientists that contributed to quantum mechanics. Now, hundred years later this topic is extremely well developed, but it is not easy. The best thing to do is to pick a good book (many books, modern books) and work through it. Then you can ask specific questions, about specific places in specific books. These questions can be answered. What you are asking now cannot be answered in a forum format - you need a book and you need to spend time to digest all this information. — Cryo, Jun 14 '19 at 17:37
The quantum theory does not contradict the wave nature of the electromagnetic radiation. A photon is a quantum of energy, but flies as a wave. — safesphere, Jun 14 '19 at 17:48
Possible duplicate of Is the wave-particle duality a real duality? — Stéphane Rollandin, Jun 14 '19 at 18:10

score 2 · Accepted Answer · answered Jun 14 '19 at 19:13

Planck's theory does not contradict the wave theory. EM waves, including visible light, have wavelengths and frequencies which can be measured by various appropriate techniques and are related by $c=f \lambda$. They have energy - Poynting vector and all that. Planck said (reluctantly!) that the energy in a particular EM wave is not arbitrary but has to be an integer number of the quantum energy $hf$.

It's like going to a shop: you can't buy 123.4 grams of sugar. It comes in packets of 500g. You can get 500 or 1000 or 1,500... grams. Light with a wavelength of, say, 500 nm comes in packets of 2.48 eV so you can get 2.48 or 4.96 or 7.44... eV. But the light in a 2.48 eV quantum is still 500 nm light, just as the sugar in a 500g packet of sugar is still sugar.

A doubt regarding Planck's quantum theory

1 Answers1