Everyday Science · 45 sec
Doppler effect
The science behind something you encounter, use, or wonder about.
The useful idea
- The useful idea
The Doppler effect (also Doppler shift) is the change in the frequency or, equivalently, the period of a wave in relation to an observer who is moving relative to the source of the wave.
- How it works
It is named after the physicist Christian Doppler, who described the phenomenon in 1842.
- Why it matters
A common example of Doppler shift is the change of pitch heard when a vehicle approaches and recedes from an observer.
Why this matters
Look for Doppler effect the next time you notice this pattern in everyday life.
Try this
Look for Doppler effect the next time you notice this pattern in everyday life.
Test your recall
Which idea belongs to the explanation of Doppler effect?
- How it works
- The useful idea — correct
- Why it matters
The Doppler effect (also Doppler shift) is the change in the frequency or, equivalently, the period of a wave in relation to an observer who is moving relative to the source of the wave.