Energy of Wave: Does Amplitude Affect E?

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The discussion centers on the relationship between wave amplitude and energy, specifically questioning if amplitude affects energy calculations. The Planck equation, E = h.f, indicates that energy is dependent solely on frequency for electromagnetic waves, with amplitude not influencing this relationship. However, energy density and energy flux, which consider both amplitude and frequency, provide a more comprehensive understanding of wave energy. In quantum terms, the Planck formula defines the minimum energy of a photon, while the overall energy is influenced by the number of photons, which correlates with amplitude. Ultimately, while amplitude does not affect the energy of individual photons, it plays a role in the total energy associated with a wave.
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Is there a equation that calculate the energy of a wave acccording to the amplitude

Another question, The plank equation E = h.f calculate the energy of any wave according to the frequency? If so, why doesn't the amplitude affect the energy (in the equation)?
 
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Plank's equation is only applicable to an Electromagnetic wave. IE Light. It was discovered that the energy per "wave" was only related to frequency of the light. As for WHY amplitude doesn't matter, that is complicated and beyond my knowledge.
 
Einstein's showed that (in his 1905 papers) light is made up of photons and each photon's energy depends on its frequency.
energy of 1 photon is h.f
 
jaumzaum said:
Is there a equation that calculate the energy of a wave acccording to the amplitude

Another question, The plank equation E = h.f calculate the energy of any wave according to the frequency? If so, why doesn't the amplitude affect the energy (in the equation)?

There are various formulas, depending on the type of the wave (EM, sound, etc). The "energy of the wave" is not a very well defined quantity. You may want to look at energy density, the energy in a specific unit volume, if it's a standing wave. Or maybe the energy flux, the energy transported by a progressive wave through a specific area in unit time.
In general these quantities depend on both the amplitude of the wave and frequency.

Now going to the quantum picture, the Plank formula gives the minimum energy (photon) that the wave may transport, exchange, etc. The total energy density or flux depends on the number of photons in the wave which can be related to the (classical) amplitude of the wave.
 
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