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here's a problem that's been troubling me all day and I really have no idea what else to do:

"Speakers A and B are vibrating in phase. They are directly facing each other, are 8.0 m apart, and are each playing a 76.0-Hz tone. The speed of sound is 343 m/s. On the line between the speakers there are three points where constructive interference occurs. What are the distances of these three points from speaker A?"

I've found the wavelength (using v=343 and f=76) to be 4.513.

I then set up three equations, that I think in theory will give me the right answer:

(w = wavelength)

(l = length (8m))

x=w

l-x=3w

y=2w

l-y=2w

z=3w

l-z=w

However, when I submitted this each answer online, I got an incorrect answer. Any help would be appreciated. thanks in advance,

Sam

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# Homework Help: Wave Problem (constructive interference)

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