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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When the coaxial is placed in a uniform magnetic field, a force is induced on each of the inner and outer conductor. The direction of the force on each conductor is given by Fleming's left-hand rule. According to this rule, if we align our hand such that the magnetic field is along the extended palm and the thumb points in the direction of current flow, then the direction in which the fingers curl will give the direction of force experienced by the conductor.

For both the inner and the outer conductor, the current flows in opposite directions. Therefore, the forces experienced by these conductors are also in opposite directions. As a result, the net force on the cable is zero. However, the forces themselves will cause a slight shift of the inner conductor to the left and the outer conductor to the right, leading to option D.

A Coaxial Cable Has an Inner Cylindrical Conductor Surrounded by Cylindrical