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Is it possible to use the undulating magnetic field of a plane-polarized standing EM wave as the source of changing magnetic flux for Faraday's law? Why or why not?

I assume that if it's possible, the coil or wire loop used in this case would be likely quite small and any electricity generated would be miniscule in amount.

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Coils were widely used as 'aerials' in radio receivers. In the 1920s and 1930s, coils of area in the order of $0.1 \text m^2$, called 'frame aerials' were often built into receiver cabinets. From the 1960s much smaller coils wound on ferrite cores were often used. The emfs induced in these coils by the oscillating magnetic fields of broadcast radio waves (of frequency in the order of 1 MHz) were processed to extract the modulation – an audio signal.

So we had Faraday's Law in action. Any electricity generated would be minuscule in amount? Maybe, but it was enough to power headphones so that you could hear a broadcast from a transmitter at least 100 miles away. That's using a 'crystal set' without amplification!

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  • $\begingroup$ Thanks Philip. As a follow-up, could you use plane-polarized sunlight as the source of changing magnetic flux to generate electricity in a coil/loop via Faraday's Law? $\endgroup$ Sep 14 at 3:41
  • $\begingroup$ As far as I know this can't be done. Devices (such as cells in the retina) that respond to such high frequencies respond to the electric field in the light. $\endgroup$ Sep 14 at 6:53

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