We present relativistic transformations of charge densities for a closed electric circuit consisting of straight sections of finite length wires. The study of charge carrier movement is made in the rest frame of carriers, and with only basic relativistic kinematics, we follow a group of charge carriers along the different segments of the circuit. From the change in inter-particle distances when moving from one wire segment to another, expressions for the charge densities are deduced. This approach aims to provide a deeper understanding of the relativistic motion of objects around a closed loop.
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2016
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