|MadSci Network: Physics|
You're hunch about the "electricity" being related to ball lightning and plasma is correct. One way to think about the operation of a microwave oven is that it's an "echo chamber" for an electric field. The field is "tuned" to get water molecules jiggling back and forth and heat substances up via molecular "friction". Plasma is a gaseous form of matter with an equal amount of positive and negative species (such as electrons and ions). Plasmas are conductive, so when you lit the toothpicks, the hot gases around the flame were allowing local conduction of the electric field within the microwave chamber; you were locally "short circuiting" the field. That's why you saw the glowing discharge or arcs around the flame. You get the same "short circuiting" effect when you place a metallic object in the microwave; hence the warnings on certain packaging. I hope your mom didn't catch you. I'm not sure she'd buy the old "I'm experimenting with plasma physics" excuse. Chris Seaman
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