The formula to calculate the speed of light

[bochoa18]

I'm doing the experiment of measuring the speed of light using eggs and a microwave but I don't know the formula to do so.

[norman40]

Hello bochoa18,

I'm assuming that you are working on the “speed of light” project described here:

https://www.sciencebuddies.org/science- ... p056.shtml

The speed of light is equal to the wavelength multiplied by the frequency of the light. This is discussed in the background section of the project at the above link.

Your microwave oven will have its frequency listed somewhere inside the oven or in the owners manual. The wavelength is the distance you measure between cooked portions of the egg whites as described in the procedure section.

I hope this helps. Please post again if you have more questions.

A. Norman

[bochoa18]

Thank you very much

[bochoa18]

Hi Mr/Mrs,
I did everything as said but my final result was of 112700. What have I done wrong?
I measured the middle, the lower and the highest points between the 2 spots of 3 eggs, I did the average of them and I got 23 cm. I multiplied by 2 (because the wavelength is the double of the distance) and the result was 46 cm, then I did 46 times 2450 MHz (the frequency) and the final result was 112700.

[norman40]

Hi bochoa18,

Before making your speed of light calculation, convert your wavelength from cm to m and convert your frequency from MHz to Hz. After the conversions, you will get 1127000000 m/s from your calculation.

As you know, the speed of light is 299792458 m/s. So, your measurement of the speed of light is high by almost a factor of four. If we assume that the microwave frequency is correct (2450 MHz) then the error must be in the wavelength measurement. Maybe you could re-check your procedure for measuring the distance between the egg hot spots.

I hope this helps. Please post again if you have more questions.

A. Norman