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Who discovered electromagnetic waves?

A:

Quick Answer

Heinrich Rudolph Hertz, a German physicist, discovered the existence of electromagnetic waves in 1887. This was a result of his expansion of James Clerk Maxwell's mathematical "Electromagnetic Theory of Light," published in 1873. The international unit of frequency, one cycle per second, is named in his honor.

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Full Answer

Hertz engineered the oscillator used to prove Maxwell's theory. The oscillator – two brass knobs connected by induction coils – created tiny sparks that jumped between the knobs when it was turned on.

He designed a circular receiving wire, also with two knobs separated by a gap, and placed it away from his oscillator. Hertz powered the oscillator, and it generated a spark that traveled the distance to the receiver, thus proving the existence of electromagnetic waves.

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