Doppler Effect
Sound Frequency Shift with Moving Sources
Observe how the frequency of sound waves changes when the source is moving relative to the observer. Listen to the pitch change and watch the wave patterns!
Stationary Source
Perceived Frequency: 440 Hz
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Observation:
When the source is stationary, the observer hears the same frequency as emitted by the source (440 Hz).
The Science Behind the Doppler Effect
Key Concepts:
The Doppler Effect is the change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source:
- Source moving toward observer: Higher perceived frequency (higher pitch)
- Source moving away from observer: Lower perceived frequency (lower pitch)
- Stationary source: No change in perceived frequency
Real-world Examples:
The Doppler Effect explains why a siren sounds higher-pitched as an ambulance approaches you and lower-pitched as it moves away. It's also used in radar, astronomy, and medical imaging.
