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SSM In Fig. 17-37, two speakers separated by distance d1 = 2.00 m are in phase. Assume the amplitudes of the sound waves from the speakers are approximately the same at the listener’s ear at distance d2 = 3.75 m directly in front of one speaker. Consider the full audible range for normal hearing, 20 Hz to 20 kHz. (a) What is the lowest frequency fmin, 1 that gives minimum signal (destructive interference) at the listener’s ear? By what number must fmin, 1 be multiplied to get (b) the second lowest frequency fmin, 2 that gives minimum signal and the third lowest frequency fmin, 3 that gives minimum signal? What is the lowest frequency fmax, 1 that gives maximum signal (constructive interference) at the listener's ear? By what number must fmax, 1 be multiplied to get (e) the second lowest frequency fmax, 2 that gives maximum signal and (f) the third lowest frequency fmax, 3 that gives maximum signal?
Figure 17-37 Problem 21.
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