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Forces of Nature

Lab Assignment: Speed of Light

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Forces of Nature Lab

Speed of Light

Goal: To determine the speed of light from observed wavelengths for electromagnetic waves of known frequency.

Materials and Procedure
  1. Follow the instructions at Science Buddies to measure the speed of light in the comfort of your own kitchen.
  2. NOTE: Popular variations on the method above use miniature marshmallows or chocolate chips evenly spread out on a plate in place of the egg whites. You may find this more interesting and less wasteful.
Data Handling
  1. Record all measurements and present your data in tabular form.
  2. Record the frequency of your microwave in Hz.
  3. Record the observed wavelengths in meters.
  4. Estimate the error in your wavelength measurements.
  5. Use the relationship speed = wavelength * frequency to determine the speed of light.
  6. Analyze the error in your measurements, given the currently accepted value for the speed of light as 2.9998 * 108 meters/second.
  1. Describe your materials and procedure.
  2. Include your data, calculations, and any averaging you used.
  3. Compare your calculated value with the established value for the speed of light. What is your error?