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At the very end of this Feynman lecture: https://www.feynmanlectures.caltech.edu/II_27.html he says that static electric and magnetic fields can store angular momentum in the field itself. In the arrangement of a charge and permanent magnet shown below in figure 27-6 there is a Poynting vector that circulates around a closed loop.

enter image description here

He even shows an experimental setup for demonstrating this effect: https://www.feynmanlectures.caltech.edu/II_17.html#Ch17-S4

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My question is if anyone has ever performed such an experiment in real life. It seems mind blowing to me that you can make a disk like that spin by storing the angular momentum in an electric and magnetic field.

The only other mention I found of this effect was this paper: http://philsci-archive.pitt.edu/16637/1/Feynman.pdf which has a slightly modified version of the experimental setup.

I have heard of the Einstein-de Hass effect https://en.wikipedia.org/wiki/Einstein%E2%80%93de_Haas_effect where you can observe the spin of electrons giving angular momentum to a macroscopic object, but this seems different.

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Not really answering your question , but abit more insight into what's going on. This is the same effect as induction pretty much. however instead of a changing magnetic field induces an electric field that moves charges INSIDE a medium, if the charges themselves are bound to the material then the total force on each of the charges will cause the macroscopic body to rotate increasing the body's angular momentum. Another worked example:

(https://i.sstatic.net/cu5xn.jpg)

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  • $\begingroup$ I wonder how this effect was discovered, because it seems at first like it is violating the conservation of angular momentum. I wonder if there are any applications, like attitude adjustment of satellites, similar to how reaction wheels work. $\endgroup$
    – Hunter
    Commented Nov 9, 2021 at 12:26
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The energy-momentum predicted by the Poynting vector for static fields cannot be detected by electromagnetic means. Only a divergency can be detected, or more precisely, the four divergency of the - in this case Belinfante - energy momentum tensor, which is actually the Lorentz four-force (force extended with power). It should in principle be detectable by its gravitational effect. However, this effect is way smaller than can conceivably be detected. The prediction is in principle testable, but not in practice.

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