WEBVTT
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in this problem on the topic off waves and sound
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, we're told that a siren can be made by
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blowing Egypt of a through 20 equally spaced holes in
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irritating disk. Yeah, we take the time that
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it takes for success of holes to move past the
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edge it as the period of sound and were given
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the frequency off the stone. We want to calculate
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the angular speed Omega off this disc. Now we
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know that the will must rotate at a frequency F
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, which is 2000 200 hearts divided by the number
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off holes, which is 20. So the frequency
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off the rotations must be 100 and 10 hunts.
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And so the angular speed omega we know is defined
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as two pi times different Quincy F. Yeah.
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So this is two pi times 100 and tin huts
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, which gives us the angular frequency off. 690
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radiance. The second. Yeah,