An AM radio detects the oscillating magnetic field of the radio wave with an antenna consisting of a coil of wire wrapped around a ferrite bar, as shown in Figure Q25.21. Ferrite is a magnetic material that “amplifies” the magnetic field of the wave. The radio antenna broadcasts waves with the electric field vertical, the magnetic field horizontal. If a radio antenna is located due north of you, how must the ferrite bar be oriented for best reception?
FIGURE Q25.21
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