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doppler effect


lesson by
magoosh expert

summary
the content provides an in-depth exploration of the doppler effect, elucidating how motion affects the perceived frequency of sound through mathematical equations and practical examples.
  • the doppler effect equation is introduced as f' = f * (v +/- vd)/(v -/+ vs), explaining the variables for emitted frequency, velocity of sound, and velocities of the source and detector.
  • practical scenarios illustrate how to apply the doppler effect equation, including a moving detector (person) and source (ambulance), and how these movements affect perceived sound frequency.
  • a series of practice problems demonstrate the application of the doppler effect in real-world situations, such as an ambulance being followed by a lawyer, the ambulance stopping, and a police pursuit.
  • the examples underscore the importance of selecting the correct operator (top or bottom) in the equation based on the direction of movement towards or away from the source or detector.
  • the final outcome of each scenario reveals how the perceived frequency changes: it remains the same when speeds are matched, increases when moving towards a stationary source, and decreases when moving away from an approaching source.
chapters
00:00
understanding the doppler effect
01:41
applying the doppler equation