Another common experience is the shift in apparent frequency of the sound of a train horn. As the train approaches, the sound of its horn is heard at a high pitch and as the train moved away, the sound of its horn is heard at a low pitch. This is the Doppler effect.
A common Physics demonstration the use of a large Nerf ball equipped with a buzzer that produces a sound with a constant frequency. The Nerf ball is then thrown around the room. As the ball approaches you, you observe a higher pitch than when the ball is at rest. And when the ball is thrown away from you, you observe a lower pitch than when the ball is at rest. This is the Doppler effect.