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"Light Drills" The sketch below shows the basic elements used by A. Michelson to measure the speed of light in the 1920's. A pulse of light hits the rotating 8-sided mirror and takes off on a round trip to a flat mirror some distance off. The pulse will be received by the detector if the rotating mirror is in the right orientation when the pulse returns. A moderate price power drill can turn at about 1200 RPM . If such a drill is used to turn the mirror, how far away does the flat mirror have to be for a pulse to be observed? How about for a Dremel that turns at 30,000 RPM? Hint: Assume the distance to the mirror (L) is large compared to the size of the 8 sided mirror.  Please explain your answer in words, not equations.
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