doppler effect

By admin_wla | Tue, 4 Feb 2014 - 12:13
The apparent change in frequency of sound or light waves, varying with the relative velocity of the source and the observer. If the source and observer draw closer together, the frequency is increased. Named for Christian Doppler, Austrian mathematician and physicist (1803-1853). Source: NASA (http://earthobservatory.nasa.gov/Glossary)