For this 3-Minute Vacation, all you need is a grape and a microwave — and to stand up and walk to your office kitchen. (Surely someone in your office brought grapes for lunch today!)
1. Take a grape and cut it in half through the equator.
2. Take one of the halves and cut it almost through lengthwise. See photo to right.
3. Pat the cut surfaces lightly with a paper towel or something to dry them a bit.
3. Take out the rotating glass turntable and its rotating plastic stand out of the microwave.
4. Place grape, cut side up, in the microwave about halfway between the center and the wall (see photo).
5. Close the door and turn on for 10 seconds.
6. Enjoy the amazing plasma light show!
So what is the science behind this light show? Well, plasma is the fourth state of matter after solids, liquids, and gases. Plasma is most often seen as lightning bolts in a dark sky and plasma science is used in high-definition televisions (i.e., plasma TVs).
Electrical discharges between the two halves of the grape vaporize the sugars in the grape causing them to combust. The continued electrical arcing between the two halves of the grape causes the combustion products to get hot enough to form plasma.
Note: this might leave a cosmetic dark spot on your microwave; when trying this out at Blue Avocado it did, but did not create any problems.
See also: Great (rather than Grape) Balls of Fire with the legendary Jerry Lee Lewis on American Bandstand (goodness gracious, great balls of fire!)