1. The highest frequency humans can hear is about 20,000 Hz. What is the wavelength of sound in air at this frequency? What is the wavelength of the lowest sounds we can hear, about 20 Hz?
2. A violin string playing the note "A" oscillates at 440 Hz.
What is the period of the string's oscillation?
3. The string of a cello playing the note C oscillates at 264 Hz. What is the period of the string's oscillation?
4. How much more intense than the threshold of hearing is a sound of 10 dB? 30 dB? 60 dB?
5. How much more intense is sound at 40 dB than sound at 0 dB?
6. How much more intense is a sound of 40 dB than a sound of 30 dB?
7. A certain note has a frequency of 1000 Hz. What is the frequency of a note one octave above it? Two octaves above it? One octave below it? Two octaves below it?
8. Starting with a fundamental tone, how many harmonics are between the first and second octaves? Between the second and third octaves? (See Figure 21.5 to get started.)