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Speed of Light with an IR LED

The speed of light has been measured many different ways using many ingenious methods. The following note describes a method which is conceptually easy to understand and fairly easy to implement. The technique is the simple time-of-flight optical pulse delay method using a short (20 nanosecond) intense infrared LED optical pulse, a high speed photodiode and preamplifier and an oscilloscope with a bandwidth between 50 - 100 MHz.”

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