Doppler effect
What Doppler effect means in Physics A-Level, as defined for AQA, OCR.
Definitions of Doppler effect
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Reference: OCR
Occurs when ultrasound is reflected from moving blood cells, so the frequency of the reflected wave is shifted by an amount Δf compared with the transmitted frequency f.
The effect through which the observed wavelengths of spectral lines reveal the motion of astronomical objects.
The change in observed frequency and wavelength when a source of waves moves relative to an observer.
Topics that use Doppler effect
- Doppler effect (A-level only) (AQA A-Level)
- Cosmology (OCR A-Level)
- Using ultrasound (OCR A-Level)
Related terms
- A-scan
- Acoustic impedance
- Acoustic impedance mismatch
- Acoustic matching
- Age of the universe
- Angle dependence of Doppler shift
- Astronomical distance units
- B-scan
Using Doppler effect in the exam
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