Nota: A tradução desta entrada está atualmente em revisão de qualidade, portanto parte do conteúdo é exibida temporariamente apenas em inglês.
Este verbete ainda não foi traduzido para o seu idioma, portanto o original é exibido abaixo.
doppler effect
This term describes a specific physical phenomenon where the perceived frequency of a wave changes based on the relative motion between the source and the observer. It is most commonly associated with sound, such as the changing pitch of a siren, but is equally critical in astronomy for measuring the velocity of stars and galaxies through redshift and blueshift.
In technical and academic registers, the term is used as a precise scientific descriptor. Because it refers to a singular physical principle, it is treated as an uncountable noun in most contexts, though it can be used countably when referring to different instances or types of the effect across various media (e.g., acoustic vs. optical).
Meanings
Examples
The siren of the passing ambulance changes pitch due to the doppler effect.
Listen to how the sound drops as the race car speeds past us; that is the doppler effect in action.
Astronomers use the doppler effect to determine if a galaxy is moving away from Earth.
I wonder if the doppler effect applies to light waves as well as sound waves.
Police radar guns rely on the doppler effect to measure the speed of vehicles.
The shift in frequency is a classic example of the doppler effect.
Wait, so the doppler effect is why the pitch sounds higher when the source is approaching?
Medical imaging devices often utilize the doppler effect to monitor blood flow in arteries.