Is Newton's 3rd law valid in non-inertial frames?
If so, then are there other cases for which Newton's 3rd law is not applicable?
The textbook case is the electromagnetic force between two relativistic charged particles. Because the electromagnetic field travels at finite speed, the interaction is delayed and usually the force two particles experience at the same time does not add up to zero. From another perspective, electromagnetic radiation carries away momentum, so the total momentum of just the charged particles is not conserved.
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