The wavelengths of AM radio waves are so long—more than 200 m—that it would be impractical to make a (1)/(4) wavelength antenna to detect their electric field. Instead, AM radios detect the magnetic field of the wave using a coil of wire. The changing flux of the wave’s magnetic field induces an emf in the coil that is detected and amplified by the receiver. If you are standing to the west of an AM station that is broadcasting a vertically polarized wave, in which direction should the axis of the coil be oriented in order to best detect the wave?

The wavelengths of AM radio waves are so long—more than 200 m—that it would be impractical to make a (1)/(4) wavelength antenna to detect their electric field. Instead, AM radios detect the magnetic field of the wave using a coil of wire. The changing flux of the wave’s magnetic field induces an emf in the coil that is detected and amplified by the receiver. If you are standing to the west of an AM station that is broadcasting a vertically polarized wave, in which direction should the axis of the coil be oriented in order to best detect the wave?

Similar questions

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