I went to a cheaper university and we use a microwave to make the standing waves and marshmallows as the detector. Incredibly you can do better than 2 sig figs if you know the freq. of the oven typically 2.65 GHz. Google marshmallow speed of light on google & you will find many descriptions of this. Just be sure to use a paper plate and to take the turn table out of the microwave when you do the experiment.Crosson said:I go to school at a cheap university, we measured the speed of light by setting up standing waves of known microwave frequencies. Google for standing waves.