The diagram below shows a moving source of sound waves.
9.1 Define Doppler-effect. (2)
9.2 In which direction is the source moving: to the left, or to the right? Motivate
your answer. (3)
9.3 You are a stationary observer of a sound source moving away from you.
How will the pitch of the sound you hear differ from its pitch if the source
was stationary? (1)
9.4 You measure a frequency which is 80% of the frequency of the sound
emitted by the source. Calculate the speed of the source if it moves away
at constant velocity from you, while you are standing next to the road.
(6)