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:

Question

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The magnetic field will exert a force on the current carrying inner conductor and the outer shell in opposite directions due to their opposite current directions. However, since the current in the outer shell is distributed over a larger area, the force per unit area is smaller than that in the inner conductor. Therefore, the inner conductor will experience a larger force to the left and the outer shell will experience a smaller force to the right. This will result in a slight shift of the inner conductor to the left and the outer conductor to the right, but no net force on the cable as a whole.

A Coaxial Cable Has an Inner Cylindrical Conductor Surrounded by Cylindrical