Does the Doppler effect come into play in any interesting or useful way if a radio transmitter or receiver is spin in a centrifuge? For example, one whose radius was the same as the wavelength of the radio signal (say, ~300 meters for 1 megahertz signal). Or, is the fact that the speed of the centrifuge will never get even close to the speed of the radio wave (speed of light) mean that nothing will happen? Would it then be more useful to consider a sound wave (speaker or microphone in a centrifuge) instead?
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1$\begingroup$ this is an application of the Doppler shift that a rotating target casuses en.wikipedia.org/wiki/Inverse_synthetic-aperture_radar $\endgroup$– hyportnexFeb 16, 2020 at 22:14
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$\begingroup$ Do you wish to demonstrate the effect? A control line aeroplane illustrates the effect well. $\endgroup$– FarcherFeb 17, 2020 at 0:07
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I believe that Doppler shift techniques can detect velocities of distant stars as small as 0.3 $\text{m s}^{-1}$, so I'm sure that the shift due to your radio transmitter being whirled would be detectable (assuming that metal walls of the centrifuge don't present a problem). The effect might not be very useful, though, except as a rather wacky way of monitoring the centrifuge speed or perhaps as a way of demonstrating to high school students that projected circular motion is sinusoidal.
answered Feb 16, 2020 at 22:45