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Hey everyone, this is question number 62 from chapter 17.
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In this problem, we're given sounds of frequencies 63 ,000, and 8 ,000 hertz.
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Rast to find the sound intensity levels needed to have the same loudness as a 40 decibel sound of frequency 1 ,000 hertz, which is a loudness of 40 phones.
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So i pasted figure 17 .38 from your textbook onto the screen so we can look at the graph that we're given its frequency versus intensity.
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So we can see our, this is pretty hard to see, but our 40 phone line is right here.
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So really we just need to refer to the graph.
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So for 60 frequency of 60 hertz, which is down here, you trace up where it hits that 40 phone line.
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And that's at about, say, 70 decibels...