Speed= distance/time
Speed= 150000m/7200s=20.83m/s(cor.to.2d.p.)
Answer:The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener.
As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound. The opposite happens when the source of sound waves moves away from the listener.
Explanation:
