Microlight
Question: When a plate with a gold decorative edge is placed in a microwave
oven, sparks appear at the gold surfaces. Why?
Answer: Any metal object acts as an antenna for electromagnetic radiation,
including microwaves. Electric currents are set up in the metal, which in turn
cause voltage differentials within and between the pieces of metal. Gold rims of
plates inevitably become scratched, and so end up with tiny gaps of less than 1
millimetre between sections of continuous gold metal.
As a result, when the plate is subjected to microwaves the voltages generated
are applied across these gaps.…
