October 21, 1999
1 min read
Add Us On GoogleAdd SciAmWhy do metal objects create sparks when placed inside a microwave oven?
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Many a careless cook has witnessed this startling phenomenon. Collier N. Smith of the National Institute of Standards and Technology in Boulder, Colo., explains:
"Good conductors, such as metal objects, act like antennas to pick up the intense electromagnetic field generated in microwave ovens for the purpose of heating food. This process can induce a large electric voltage in the conductor, which then can arc to the wall of the oven or to other conductive objects in the oven, thereby creating the observed sparks
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