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| Water waves approach an underwater "shelf" where the velocity changes from 2.8 m/s to 2.1 m/s. If the incident wave crests make a 34-degree angle with the shelf, what will the angle of refraction be? | ??? |
| A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 1.5 s after shouting. Estimate the length of the lake. | ??? |
| A sailor strikes the side of his ship just below the waterline. He hears the echo of the sound reflected from the ocean floor directly below 2.0 s later. How deep is the ocean at this point? | ??? |
| Sound with a frequency of 442 Hz travels through an iron beam. Find the wavelength of the sound in iron. | ??? |
| A bat emits a sound whose frequency is 91 kHz. The speed of sound in air at 20 degrees Celsius is 343 m/s. However, the air temperature is 35 degrees Celsius, so the speed is not 343 m/s. Find the speed of sound at this temperature and determine the wavelength of the sound. | ??? |
| The distance between a loudspeaker and the left ear of a listener is 2.70 m. (a) Calculate the time required for sound to travel this distance if the air temperature is 20 degrees Celsius. (b) Assuming that the sound frequency is 523 Hz, how many wavelengths are contained in this distance? | ??? |
| Calculate the wavelengths in air at 20 degrees Celsius for sounds in the maximum range of human hearing, 20 Hz to 20,000 Hz. | ??? |
| What is the wavelength of a 10-MHz ultrasonic wave? | ??? |
