14.1 Speed of Sound, Frequency, and Wavelength
Is the speed of sound dependent on its frequency?
14.3 Doppler Effect and Sonic Booms
True or false—The Doppler effect occurs only when the sound source is moving.
True or false—The observed frequency becomes infinite when the source is moving at the speed of sound.
You are driving alongside a train. You hear its horn at a pitch that is lower than the actual frequency. What should you do to match the speed of the train? Why?
- In order to match the speed of the train, one would need to increase or decrease the speed of his/her car because a lower pitch means that either the train (the source) is moving away or that you (the observer) are moving away.
- In order to match the speed of the train, one would need to drive at a constant speed because a lower pitch means that the train and the car are at the same speed.
14.4 Sound Interference and Resonance
True or false—An open-pipe resonator has more overtones than a closed-pipe resonator.