Need Help Remembering An Equation

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Discussion Overview

The discussion centers around the equation for converting frequency into energy, specifically in the context of electromagnetic waves and its implications for mass and wave-particle duality. Participants explore the relationship between energy, frequency, and mass-energy equivalence.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant proposes the equation E = hf for converting frequency to energy, seeking confirmation.
  • Another participant confirms E = hf and assumes it pertains to electromagnetic waves.
  • A participant questions whether mc^2 = hf implies that all mass is equivalent to electromagnetic waves.
  • Another participant challenges this interpretation, clarifying that while all matter has an associated wavelength, rest mass energy cannot be directly compared to the energy of an electromagnetic wave.
  • Further elaboration includes the momentum of photons and the generalized equation for massive particles, E^2 = m^2 c^4 + p^2 c^2, indicating the complexity of energy beyond rest mass.

Areas of Agreement / Disagreement

Participants generally agree on the equation E = hf for electromagnetic waves, but there is disagreement regarding the implications of mass-energy equivalence and the interpretation of wave-particle duality.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the relationship between mass and electromagnetic waves, as well as the scope of energy definitions in different contexts.

Hertz
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Does anyone happen to know the equation to convert frequency into energy?
I think it's something like: E = hf, but I'm not sure.

Any help is appreciated :)
 
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Hertz said:
E = hf

Yup. I assume you mean for EM waves?
 
Yup, is that the right equation?
 
Yes.
 
So this means that mc^2 = hf right?
So does this mean that everything with mass is actually an EM wave? Sorry I don't know a whole lot, I'm still in 11th grade :\
 
No, that's not what it means, that's why I asked if you meant for EM waves.
While yes, all matter does have an associated wavelength, but no, you can't compare the rest mass energy to the energy for an EM wave.

You should read about http://en.wikipedia.org/wiki/Wave-particle_duality" if you are curious.

For photons, [tex]E=h f[/tex] where the momentum of a photon is given by,
[tex]p = {E \over c}[/tex]

Generalized to massive particles, we get
[tex]\lambda = {h \over p}[/tex]

Where [tex]\lambda[/tex] is the associated wavelength.

In general, energy is not just the rest mass energy and also includes a momentum term, so for our massive particles we have: [tex]E^2 = m^2 c^4 + p^2 c^2[/tex]
 
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