What principle reconciles the force experienced by a charged particle when observed from different inertial frames?

Answer

The Lorentz transformation equations.

The Lorentz transformation governs how space and time change between reference frames, causing charge densities (and thus electric fields) to transform in a way that accounts for the perceived magnetic force in the moving frame.

What principle reconciles the force experienced by a charged particle when observed from different inertial frames?
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