Development
Doppler first proposed the effect in 1842 in his treatise "Über das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels" (On the coloured light of the binary stars and some other stars of the heavens). The hypothesis was tested for sound waves by Buys Ballot in 1845. He confirmed that the sound's pitch was higher than the emitted frequency when the sound source approached him, and lower than the emitted frequency when the sound source receded from him. Hippolyte Fizeau discovered independently the same phenomenon on electromagnetic waves in 1848 (in France, the effect is sometimes called "l'effet Doppler-Fizeau" but that name was not adopted by the rest of the world as Fizeau's discovery was three years after Doppler's). In Britain, John Scott Russell made an experimental study of the Doppler effect (1848).
Read more about this topic: Doppler Effect
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“And then ... he flung open the door of my compartment, and ushered in “Ma young and lovely lady!” I muttered to myself with some bitterness. “And this is, of course, the opening scene of Vol. I. She is the Heroine. And I am one of those subordinate characters that only turn up when needed for the development of her destiny, and whose final appearance is outside the church, waiting to greet the Happy Pair!””
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