Speed of Light

This experiment uses the Foucault Method to determine the speed of light. Laser light passes through a series of lenses to produce an image of the light source at a measured position. The light is then directed to a rotating mirror, which reflects the light to a fixed mirror at a known distance from the rotating mirror. The laser light is reflected back through its original path and a new image is formed at a slightly different position.

The difference between final/initial positions, angular velocity of the rotating mirror and distance traveled by the light are then used to calculate the speed of light.

Grade Level: CollegeHigh School

Subject: Physics

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Speed of Light Experiment

Speed of Light Experiment

The complete solution for determining the speed of light using a laser light and a high speed rotating mirror.

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