1. A student shouts across a canyon and hears his echo 4 sec later. If the speed of sound is 343 m/s, how wide is the canyon?
2. A 440 Hz frequency sound is heard. What is its wavelength is the temperature is 20°C? If it is -10°C?
3. A train blows a 400 Hz horn as it approaches an intersection at 36 m/s. What frequency is heard by a stationary observer? What is heard by the stationary observer if it now is receding?
4. A 5000 Hz sound wave is directed toward a an object moving at 3.5 m/s toward the stationary source. What is the frequency detected by the moving object?
5. A stone is dropped in a mine shaft 15 m deep. The speed of sound is 343 m/s. How long does it take to hear the echo?
6. A closed tube resonates in its fundamental. What is the length of the tube if the wavelength is 78 cm? What would be its length if it were an open tube?
7. A guitar string 1.2 m long vibrates with a wave speed of 720 m/s. What is the frequency of the first three harmonics?
8. An open pipe 0.5 m long is used to produce the first three harmonics. What are their frequencies if the speed of sound is 340 m/s?
9. Repeat number seven using a closed pipe 0.3 m long. Remember, the first three harmonics are the fundamental, third harmonic, and the fifth harmonic.
10. A student uses a water-filled tube 100 cm high to determine the speed of sound. A fundamental is found to occur when the water level is 83 cm high and a 512 Hz tuning fork is used to produce the sound. What is the experimentally determined speed of sound?

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