Waves, Sound and Light: Light Waves
Light Waves: Audio Guided Solution
The German-born, American physicist Albert Michelson devoted much of his life to the accurate measurement of the speed of light. In 1923, he positioned mirrors and detectors on two different California mountains positioned nearly 35 km (nearly 22 miles) apart. Using a sophisticated timing method of involving the rotating of octagonal mirrors, Michelson determined the speed of light to be 299,774 km/sec. At this speed, estimate the time it takes light to travel 35 km between mountains.
Audio Guided Solution
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1.2 x 10-4 s or 120 µs
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