In figure OQ18.1 (page 566), a sound wave of wave-lenght 0.8 m divides into two equal parts that recombine to interfere constructively, with the original difference between their path lengths being |r2 r1| = 0.8 m. Rank the following situations according to the intensity of sound at the receiver from the highest to the lowest. Assume the tube walls absorb no sound energy. Give equal ranks to situations in which the intensity is equal. (a) From its original position, the sliding section is moved out by 0.1 m. (b) Next it slides out an additional 0.1 m. (c) It slides out still another 0.1 m. (d) It slides out 0.1 m more.

Two identical loudspeakers 10.0 m apart are driven by the same oscillator with a frequency of f = 21.5 Hz (Fig. P17.6) in an area where the speed of sound is 344 m/s. (a) Show that a receiver at point A records a minimum in sound intensity from the two speakers. (b) If the receiver is moved in the plane of the speakers, show that the path it should take so that the intensity remains at a minimum is along the hyperbola 9x2 16y2 = 144 (shown in red-brown in Fig. P17.6). (c) Can the receiver remain at a minimum and move very far away from the two sources? If so, determine the limiting form of the path it must take. If not, explain how far it can go. Figure P17.6

Two sources as in phase and emit waves with =0.42 m. Determine whether constructive or destructive interference occurs at points whose distances from the two sources are (a) 0.84 and 0.42 m, (b) 0.21 and 0.42 m, (c) 1.26 and 0.42 m, (d) 1.87 and 1.45 m, (e) 0.63 and 0.84 m and (f) 1.47 and 1.26 m.

Consider detectors of water waves at three locations A, B, and C in Active Figure 13.23b. Which of the following statements is true? (a) The wave speed is highest at location A. (b) The wave speed is highest at location C. (c) The detected wavelength is largest at location B. (d) The detected wavelength is largest at location C. (e) The detected frequency is highest at location C. (f) The detected frequency is highest at location A.

A sound wave in air has a pressure amplitude equal to 4.00 103 Pa. Calculate the displacement amplitude of the wave at a frequency of 10.0 kHz.

During a 4th of July celebration, an M80 firework explodes on the ground, producing a bright flash and a loud bang. The air temperature of the night air is TF=90.00F . Two observers see the flash and hear the bang. The first observer notes the time between the flash and the bang as 1.00 second. The second observer notes the difference as 3.00 seconds. The line of sight between the two observers meet at a right angle as shown below. What is the distance x between the two observers?

A speaker is placed at the opening of a long horizontal tube. The speaker oscillates at a frequency f, creating a sound wave that moves down the tube. The wave moves through the tube at a speed of v=340.00 m/s. The sound wave is modeled with the wave function s(x,t)=smaxcos(kxt+) . At time t=0.00 s , an air molecule at x=3.5 m is at the maximum displacement of 7.00 nm. At the same time, another molecule at x=3.7 m has a displacement of 3.00 nm. What is the frequency at which the speaker is oscillating?

(a) What is the speed of sound in a medium where a 100kHz frequency produces a 5.96cm wavelength? (b) Which substance in Table 17.1 is this likely to be?

Two-point sources emit sound waves of 1 m wavelengths. The sources are pointed at each other. The sources, 2 m apart, emit waves that are in phase with each other at the instant of emission. a) Where, along the line between the sources are the waves out of phase with each other by pi radians? b) If the emitted wavelength changes to 0.5 m, where are the waves out of phase with each other by π/2 radians?