The Doppler effect, named after Christian Andreas Doppler, is the apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves.
The siren on a passing emergency vehicle will start out higher than its stationary pitch, slide down as it passes, and continue lower than its stationary pitch as it recedes from the observer.
For more information about the topic Doppler effect, read the full article at Wikipedia.org, or see the following related articles:
Breaking wave In physics, a breaking wave is a wave whose amplitude reaches a critical level at which some process can suddenly start to occur that causes large ... >
read more
Electromagnetic radiation Electromagnetic radiation is a propagating wave in space with electric and magnetic components. These components oscillate at right angles to each ... >
read more
Alpha wave Alpha waves are electromagnetic oscillations in the frequency range of 8-12 Hz arising from synchronous and coherent (in phase / constructive) ... >
read more
Seismic wave A seismic wave is a wave that travels through the Earth, most often as the result of a tectonic earthquake, sometimes from an explosion. There are ... >
read more
Redshift In physics and astronomy, redshift is an observed increase in the wavelength of electromagnetic radiation received by a detector compared to that ... >
read more
Light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, ... >
read more
Shock wave In a supersonic flow the compression of a nonreacting gas can be most simply modelled as an isentropic or Prandtl-Meyer compression, or as a shock ... >
read more
Speed of sound The speed of sound is a term used to describe the speed of sound waves passing through an elastic medium. The speed varies with the medium employed ... >
read more
Corona In astronomy, a corona is the luminous plasma "atmosphere" of the Sun or other celestial body, extending millions of kilometres into space, most ... >
read more
Acoustics Acoustics is the branch of physics concerned with the study of sound (mechanical waves in gases, liquids, and solids). A scientist who works in the ... >
read more
Note: This page refers to an article that is licensed under the GNU Free Documentation License. It uses material from the article Doppler effect at Wikipedia.org. See the Wikipedia copyright page for more details. Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.
Recommend this page on Facebook, Twitter,
and Google +1:
Other bookmarking and sharing tools: