8.2.7

Doppler Effect

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The Doppler Effect

The Doppler effect describes the phenomenon of the observed wavelength and frequency of waves changing when the source of the waves is moving with respect to an observer.

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Types of waves

  • The Doppler effect can be experienced with all types of waves.
  • The wavelength and frequency of the waves do not actually change.
Illustrative background for Approaching vs receding sourcesIllustrative background for Approaching vs receding sources ?? "content

Approaching vs receding sources

  • When the source of the waves is approaching, the frequency shifts upwards for observers.
  • When the source of the waves is receding, the frequency shifts downwards for observers.
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Doppler equation

  • The observed frequency fof_o is given by the equation:
    • fo=vv±vsff_o=\frac{v}{v\pm v_s}f
  • Where fsf_s is the frequency at the source, vv is the speed of the wave and vsv_s is the speed of the source.
  • The minus sign is used for motion toward the observer and the plus sign for motion away from the observer, producing the appropriate shifts up and down in frequency.

Jump to other topics

1Physical Quantities & Units

2Measurement Techniques

3Kinematics

4Dynamics

5Gravitational Fields

6Deformation of Solids

7Thermal Physics

8Oscillations

9Communication

10Electric Fields

11Current Electricity

12Magnetic Fields

13Modern Physics

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