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## Main Question or Discussion Point

I have some doubts about whether Planck's relation (E=hf) applies to radio waves. This has been bugging me because trying to apply Planck's relation to radio frequency results in some inconsistencies that I've been unable to resolve. BTW, I have no physics training, so please go easy on me

Radio waves can be generated by alternating current. The frequency of the current is usually determined by a crystal or a LC circuit. For example, a 28 MHz crystal will generate an alternating current at 28 MHz (hopefully). When used in a radio transmitter, the resulting RF is 28 MHz.

Is there a relationship between the frequency of this radio wave and its energy? In other words, does Planck's relation work here? And if so, why? Assuming it does, would the energy of this radio wave be 1.86e-26 J.s?

As I understand it, Planck's relation only works with electron transition levels. Here's where I see a problem with applying Planck's relation to RF: We can generate RF with very specific frequencies, which translates into specific energies. But we know the energies from electrons jumping down orbitals are quantized. They can emit energy at only a finite number of frequencies, so I don't see how it's possible for radio waves to have an infinite number of frequencies.

But for the sake of argument, let's say there it is possible for an atom to emit energy at any arbitrary frequency. How can the alternating current frequency (28 MHz) cause electrons in an atom to jump up and down to the right orbital to emit energy at that precise frequency?

So far the only conclusion that makes sense is that Planck's relation has nothing to do with radio waves, and that comparing electron energy levels with RF energy is comparing apples and oranges.

Thanks!

Radio waves can be generated by alternating current. The frequency of the current is usually determined by a crystal or a LC circuit. For example, a 28 MHz crystal will generate an alternating current at 28 MHz (hopefully). When used in a radio transmitter, the resulting RF is 28 MHz.

Is there a relationship between the frequency of this radio wave and its energy? In other words, does Planck's relation work here? And if so, why? Assuming it does, would the energy of this radio wave be 1.86e-26 J.s?

As I understand it, Planck's relation only works with electron transition levels. Here's where I see a problem with applying Planck's relation to RF: We can generate RF with very specific frequencies, which translates into specific energies. But we know the energies from electrons jumping down orbitals are quantized. They can emit energy at only a finite number of frequencies, so I don't see how it's possible for radio waves to have an infinite number of frequencies.

But for the sake of argument, let's say there it is possible for an atom to emit energy at any arbitrary frequency. How can the alternating current frequency (28 MHz) cause electrons in an atom to jump up and down to the right orbital to emit energy at that precise frequency?

So far the only conclusion that makes sense is that Planck's relation has nothing to do with radio waves, and that comparing electron energy levels with RF energy is comparing apples and oranges.

Thanks!