Measuring the Speed of Light in Your Microwave

Are you ready to take a break from doing your taxes, but don't want to quite turn off the part of your brain you use to do math?

If so, GeekMom Kathy Ceceri has found a physics experiment you can do in your microwave oven with that stale chocolate candy you might still have leftover from Valentines Day!

Here's what you'll need:

• A microwave oven.
  
• A microwave safe plate or container.
  
• Chocolate, either in bar form or a number of other pieces.
  
• A ruler with a centimeter scale.
  

Here's how to do the experiment:

1. If it has one, remove the revolving tray from your microwave, or simply disable it from rotating.
   
   
2. On a plate, heat a large chocolate bar, or a number of chocolate pieces set in a rectangular pattern, on full power until it starts to melt in two or three places – this will probably only take about 20 seconds. (Don't let your microwave run for too long, or else you may be doing quite a bit of post-experiment cleanup. We won't be held responsible for cleaning up your "accident" and now, you can't say you weren't warned.... or never pointed to the FDA's guide on using your microwave safely....)
   
   
3. Remove the chocolate from the microwave and measure the distance between the melted spots. In centimeters.
   
   
4. Assume your microwave is a standard one which has a frequency of 2.45 gigahertz (you could check this in your manual if you know where it is to confirm this figure - it may be shown as 2,450 megahertz.)
   
   
5. Enter the measurement and alter the default data as needed in our handy tool below, then click the "Calculate" button.
   
   
6. Compare your answer to 299,792,458 meters per second. The speed of light!
   

Here's that tool:

The Microwave Chocolate Physics Experiment
Input Data	Values
Distance Between Melted Spots in Microwaved Chocolate [cm]
Frequency of Your Microwave Oven [MHz]

The Speed of Light
Calculated Results	Values
Estimated Speed of Light [meters/second]

Who said doing taxes couldn't be fun!