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The Doppler Effect quiz

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  • What is the Doppler effect?
    The Doppler effect is the change in frequency of sound due to the relative motion between the sound source and the listener.
  • What happens to the frequency heard when the listener moves towards the sound source?
    The listener hears a higher frequency than the source produces when moving towards the sound source.
  • What is the equation for the Doppler effect?
    The equation is FL = (v + vL) / (v + vS) * FS, where FL is the frequency heard, FS is the source frequency, v is the speed of sound, vL is listener velocity, and vS is source velocity.
  • What is the frequency heard if both the listener and the source are stationary?
    The frequency heard is equal to the frequency produced by the source.
  • What causes the Doppler effect?
    The Doppler effect is caused by relative motion between the sound source and the listener.
  • What happens to the frequency heard when the listener moves away from the sound source?
    The listener hears a lower frequency than the source produces when moving away from the sound source.
  • What is the value of v in the Doppler effect equation?
    v is the speed of sound, typically 343 meters per second in air.
  • What does vL represent in the Doppler effect equation?
    vL represents the velocity of the listener.
  • What does vS represent in the Doppler effect equation?
    vS represents the velocity of the sound source.
  • How does the direction of positive velocity get established in Doppler effect problems?
    The direction of positive is always from the listener to the source.
  • What happens to sound waves when the source moves towards the listener?
    The waves get crammed together in front of the source, resulting in a higher frequency heard by the listener.
  • What happens to sound waves when the source moves away from the listener?
    The waves get stretched out behind the source, resulting in a lower frequency heard by the listener.
  • In the practice problem, what was the observed frequency by the motorcycle rider?
    The observed frequency was 600 Hz.
  • In the practice problem, what was the frequency produced by the stationary car?
    The frequency produced by the car was 550 Hz.
  • What was the calculated speed of the motorcycle rider towards the sound source in the practice problem?
    The calculated speed was 31.2 meters per second.