What is the Doppler Effect?
changes in frequency
Doppler Effect
The Doppler Effect is the change in frequency that occurs when a source is moving relative to an observer.
Example #1
Source moving toward blue, the wavelength is decreasing and the frequency is increasing.
Source moving toward red, the wavelength is increasing and the frequency is decreasing.
Example #2
The first picture shows an object at rest, the second is an object moving.
Example #3
The closer it is the higher the frequency, The farther it is the lower the frequency.
Facts
- sound travels in waves
- higher frequency when the source is moving toward observer
- lower frequency when the source is moving away from observer
The Doppler Effect: what does motion do to waves?