A coaxial cable has an inner cylindrical conductor surrounded by cylindrical insulation and an outer cylindrical conducting shell. The outer shell carries the same current but in the opposite direction from that in the inner conductor as shown. If the coaxial cable sits in a uniform magnetic field directed upwards with respect to the cable, the effect of the field on the cable is

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The current in the inner conductor and outer shell creates a magnetic field in the opposite direction to the uniform magnetic field. Since the inner and outer currents are in opposite directions, their magnetic fields also cancel each other out. Thus, there is no net magnetic force on the cable. However, the slight shift of the inner conductor to the left and the outer conductor to the right is due to a phenomenon called the "Lorentz force," which is a result of the interaction between the magnetic field and the charges in the conductors.

A Coaxial Cable Has an Inner Cylindrical Conductor Surrounded by Cylindrical