Question

Which of these would be best explained by the Doppler effect? A) The change in frequency as you shorten a guitar string. B) The change in pitch heard as an ambulance approaches you. C) The change in volume as a train pulls away from the station. D) The change in speed of a sound wave as it travels from air into water

Answer 1

B)

Doppler effect is about the apparent change in frequency. The change in pitch heard as an ambulance approaches you is an example of this