1. Determine the lower and higher wavelength limits of the average person who can hear sound waves ranging in frequency from about 20 Hz to 20,000 Hz. The speed of sound is 340 m/s. Ans: 17 m; 0.017 m
2. Radar waves with a 3.4 cm wavelength are sent out from a transmitter with a speed of 3 x 10⁸ m/s. What is their frequency? Ans: 8.82 x 10⁹ Hz
3. Water waves in a tank are 10 cm long. If they pass a point at the rate of 3.75 waves/sec, what is their speed? Their period? Ans: 0.375 m/s; 0.27 sec
4. A wave is reflected from a wall 700 m away. The reflected wave is detected 5 sec after the original wave’s transmission What is the speed of the wave? If the wave has a period of 0.002 sec, what is its wavelength? Ans: 280 m/s; 0.56 m
5. A man tries to determine the distance to an island offshore by using his knowledge of physics and wave motion. He determines that it takes 56 sec for a wave to go from his position to the island. He estimates the distance between wave crests to be 5 m. He notes that it takes 2 sec for successive wave crests to pass him. Knowing this information, how far away is the island? Ans: 140 m

Waves Notes

Waves Sample Problems