Energy of Wave: Does Amplitude Affect E?

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SUMMARY

The discussion centers on the relationship between wave energy, amplitude, and frequency, specifically referencing Planck's equation E = h.f. It is established that this equation calculates the energy of electromagnetic waves, such as light, based solely on frequency, while amplitude does not directly affect the energy of individual photons. The conversation highlights that energy density and energy flux are more relevant metrics when considering amplitude's impact on wave energy. Additionally, it is noted that the total energy density or flux is influenced by the number of photons, which correlates with the classical amplitude of the wave.

PREREQUISITES
  • Understanding of Planck's equation (E = h.f)
  • Familiarity with concepts of energy density and energy flux
  • Basic knowledge of electromagnetic waves and photons
  • Awareness of wave mechanics and amplitude effects
NEXT STEPS
  • Research energy density calculations for standing waves
  • Explore energy flux in progressive waves
  • Study the relationship between amplitude and photon count in quantum mechanics
  • Investigate different wave types and their energy equations
USEFUL FOR

Physicists, students of quantum mechanics, and anyone interested in the principles of wave energy and its dependence on frequency and amplitude.

jaumzaum
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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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