The original derivation of the equation for this effect proceeds by considering the frame variation of distance between surfaces of constant phase; that equation dictates that this phenomenon is governed by the parameter c over c plus c, where c is the phase speed and v is the radial velocity of the source with respect to the observer.
This phenomenon allows estimation of the temperature of a line spectrum emitter via its namesake broadening. Buys Ballot confirmed this effect in one medium, while Fizeau, a sometime namesake of this effect, measured it for light. The original derivation of the equation for this effect proceeds by considering the frame variation of distance between surfaces of constant phase; that equation dictates that this phenomenon is governed by the parameter c over c plus c, where c is the phase speed and v is the radial velocity of the source with respect to the observer. For 10 points, name this phenomenon in the classical version of which the frequency of a wave changes when its source is moving.
This phenomenon allows estimation of the temperature of a line spectrum emitter via its namesake broadening.
the {Doppler}-Fizeau {effect} [or {Doppler shift}; prompt on {Doppler}]