English Dictionary |
DOPPLER EFFECT
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IPA (US): |
Dictionary entry overview: What does Doppler effect mean?
• DOPPLER EFFECT (noun)
The noun DOPPLER EFFECT has 1 sense:
1. change in the apparent frequency of a wave as observer and source move toward or away from each other
Familiarity information: DOPPLER EFFECT used as a noun is very rare.
Dictionary entry details
Sense 1
Meaning:
Change in the apparent frequency of a wave as observer and source move toward or away from each other
Classified under:
Nouns denoting natural phenomena
Synonyms:
Doppler effect; Doppler shift
Hypernyms ("Doppler effect" is a kind of...):
propagation (the movement of a wave through a medium)
Context examples
Subtle changes in the wavelength of this light due to the Doppler effect reveal the motions of the gas in the disc.
(ALMA Discovers Trio of Infant Planets around Newborn Star, ESO)
A classic Doppler effect example is how the pitch of a police siren drops once it passes.
(Astronomers Study How Quasars Are Powered by Accretion Disks, The Titi Tudorancea Bulletin)
Diagnostic imaging that uses sound waves (ultrasound) applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow.
(Doppler Ultrasound, NCI Thesaurus)
This shift creates a very subtle Doppler effect in the light dispersed by stars, which, by using CARMENES, can be measured with an accuracy of 1 metre per second—equivalent to walking speed, or, 3.6km per hour.
(Researchers find two new planets with masses similar to Earth’s near a small neighbouring star, University of Granada)
The researchers used the Doppler effect to measure these lines and observe the velocity of gas feeding into the disk, toward the black hole.
(Astronomers Study How Quasars Are Powered by Accretion Disks, The Titi Tudorancea Bulletin)
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