1. A periodic wave has a period of 0.50 s. What is the wave frequency? 2. Waves moving on a lake have a speed of 3 m/s and a distance of 1.75 m between adjacent crests. a. What is the frequency of the waves? b. What is the period of the waves? 3. A sound wave has a frequency of 2500 Hz. What is the distancce between crests or compressions? (Assume that the speed of sound is 344 m/s.) 4. Compute the wavelength in air of ultrasound with a frequency of 60 kHz if the speed of sound is 344 m/s, 5. During a thunderstorm, a 5.5 s difference between observing a lightening flash and hearing the resultant thunder. How far away in km and mi was the lightening flash? (The speed of sound is 344 m/s) 6. A sound wave has a frequency of 250 Hz and a wavelength of 2.5 m. What is the speed of the wave? 7. The upper limit for human hearing is about 20,000 Hz. What is the wavelength, in m for this wave? 8. An echo is heard from a building 8 s after you blow the cars horn. How far away is the building? 9. The distance between the center of condensation and the center of an adjacent rarefaction is 5 m. If the frequency is 300 Hz, what is the speed of the wave front? 10. A sonar signal is sent from a ship and the signal returns from the bottom 3.75 s later. How deep is the ocean if the speed of sound in water is 1,530 m/s?