Larmor's theorem

Larmor's theorem

[′lär·mȯrz ‚thir·əm]
(electromagnetism)
The theorem that for a system of charged particles, all having the same ratio of charge to mass, moving in a central field of force, the motion in a uniform magnetic induction B is, to first order in B, the same as a possible motion in the absence of B except for the superposition of a common precession of angular frequency equal to the Larmor frequency.
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