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Quote from: hamdani yusuf on 08/06/2023 03:50:26 There's no adequate justification to extrapolate it to other type of power or energy, such as gravitational potential energy.Do you know that gravity affects photon energy?
There's no adequate justification to extrapolate it to other type of power or energy, such as gravitational potential energy.
Afaik, it changes the energy by affecting the frequency
Planck's energy equation E = n.h.f,
Where does the n come from? E = hf in my universe.
Planck's HypothesisIn 1900 Max Planck proposed a formula for the intensity curve which did fit the experimental data quite well. He then set out to find a set of assumptions -- a model -- that would produce his formula. Instead of allowing energy to be continuously distributed among all frequencies, Planck's model required that the energy in the atomic vibrations of frequency f was some integer times a small, minimum, discrete energy,Emin = hfwhere h is a constant, now known as Planck's constant,h = 6.626176 x 10-34 J sPlanck's proposal, then requires that all the energy in the atomic vibrations with frequency f can be written asE = n h fwhere n in an integer, n = 1, 2, 3, . . . No other values of the energy were allowed. The atomic oscillators could not have energy of (2.73) hf or (5/8) hf.This idea that something -- the energy in this case -- can have only certain discrete values is called quantization. We say that the energy is quantized. This is referred to as Planck's quantum hypothesis. "Quantum" means how great or of a fixed size.
1 photon -> 1 electron1 electron -> 1 photon http://www.phys.ttu.edu/~slee/3301/2018_Fall/F18_3301_Lecture4.pdf
Quote from: hamdani yusuf on 08/06/2023 12:05:31Afaik, it changes the energy by affecting the frequencyThe statement is meaningless.How could it affect one but not the other?The statement is meaningless.
Where does the n come from? E = hf in my universe. But that doesn't mean energy is quantised. Planck's model describes the energy levels available to a particle constrained in a box. Obviously if you have two particles with the same frequency in the box, you have twice as much energy, but the box can be any size you like and a free particle can have any amount of energy you care to give it.So haviong establioshed, for the umpteenth time, that energy is not necessarily quantised, we have reduced the question "where does the quantisation come from" tothe same level of pointlessness as "why are unicorns born feet-first?"
Some sources mention that n is the number of photons.
A universe containing only 1 photon doesn't allow anyone to exist, let alone to think.
Gravitational potential energy and electrostatic potential energy has no frequency in their equations.
In energy equation E=n.h.f, you can change E with constant f by changing n.
hf is the energy of a photon. Obviously if you have more photons in a box, you have more energy in the box. That doesn't mean that energy is quantised, only that photons are.
Quote from: alancalverd on 09/06/2023 08:53:36hf is the energy of a photon. Obviously if you have more photons in a box, you have more energy in the box. That doesn't mean that energy is quantised, only that photons are.Can you add radiation energy by half a photon?
You could ad a photon with 0.5f to the box, but it would still be a whole photon.
No. It means that a quantum of radiation has a particular energy, and that energy is directly related to the frequency of the wave that models the propagation of that quantum.
That quantization was thought to be necessary to explain the energy distribution of black body radiation.
Planck didn't really suggest all e-m radiation was quantised and it certainly wasn't required to explain Blackbody radiation. Taking an extract from your quotation - he only required that the energy in the atomic vibrations of frequency f was some integer times a small, minimum, discrete energy,. To paraphrase that - all Planck advocated for was quantised oscillators in the walls.
In 1900, the British physicist Lord Rayleigh derived the λ−4 dependence of the Rayleigh?Jeans law based on classical physical arguments, relying upon the equipartition theorem. This law predicted an energy output that diverges towards infinity as wavelength approaches zero (as frequency tends to infinity). Measurements of the spectral emission of actual black bodies revealed that the emission agreed with Rayleigh's calculation at low frequencies but diverged at high frequencies; reaching a maximum and then falling with frequency, so the total energy emitted is finite. Rayleigh recognized the unphysical behavior of his formula at high frequencies and introduced an ad hoc cutoff to correct it, but experimentalists found that his cutoff did not agree with data.[1][3] Hendrik Lorentz also presented a derivation of the wavelength dependence in 1903. More complete derivations, which included the proportionality constant, were presented in 1905 by Rayleigh and Sir James Jeans and independently by Albert Einstein.[3] Rayleigh believed that this discrepancy could be resolved by the equipartition theorem failing to be valid for high-frequency vibrations, while Jeans argued that the underlying cause was matter and luminiferous aether not being in thermal equilibrium.[3]https://en.m.wikipedia.org/wiki/Rayleigh%E2%80%93Jeans_law
The concept of quantum of radiation was created after the discovery of quantization in radiation energy.
So Planck wanted quantised oscillators in his cavity walls only. Radiation in general or that exists elsewhere in the world (not inside a cavity at thermal equilibrium with cavity walls) was under no obligation to be quantised.