Study guide

0, P ViV, famm) [T e10jog s [atu-tn fo=fs( J L (3315) 273K p T A Arrt V.4V, o The range of human hearing extends from approximately 20 Hz to 20 000 Hz. Find the wavelengths of these extremes at a temperature of 27C. : The intensity level produced by a jet airplane at a certain location is 150 dB. (a) Calculate the intensity of the sound wave generated by the jet at the given location. (b) Compare the answer to part (a) to the threshold of pain and explain why employees directing jet airplanes at airports must wear hearing protection equipment. An outside 1loudspeaker (considered a small source) emits sound waves with a power output of 100 W. (a) Find the intensity 10.0 m from the source. (b) Find the intensity level in decibels at that distance. (c) At what distance would you experience the sound at the threshold of pain, 120 dB? A commuter train passes a passenger platform at a constant speed of 40.0 m/s. The train horn is sounded at its characteristic frequency of 320. Hz. (a) What overall change in frequency is detected by a person on the platform as the train moves from approaching to receding? (b) What wavelength is detected by a person on the platform as the train approaches? Two trains on separate tracks move toward each other. Train 1 has a speed of 1 80hx 102 km/h: train 2, a speed of 90.0 km/h. Train 2 blows its horn, emitting a frequency of 5.00 x 102 Hz. What is the frequency heard by the engineer on train 12 A stretched string of length L is observed to vibrate in five equal segments when driven by a 30.-Hz oscillatr. What oscillator frequency will set up a standing Gvg#so that the string vibrates in three segments? The overall length of a piccolo is 32.0 cm. The resonating air column vibrates as in a pipe that is open at both ends. (a) Find the frequency of the lowest note a piccolo can play. (b) Opening holes in the side effectively shortens the length of the resonant column. If the highest note a Piccolo can sound is 4.00 x 10 3 Hz, find the distance between adjacent antinodes for this mode of vibration. A pipe open at both ends has a fundamental frequency of 3.00 x 102 Hz when the temperature is 0C. (a) What is the length of the pipe? (b) What is the fundamental frequency at a temperature of 30.0 e : e Lo