Microwave Sparking and Melting Wire
Date: Winter 2009-2010
My question is that I removed a very old built in microwave. on the back was a piece
of wire, thin but rigid. I clipped it off to save it as the 12" piece of wire lay
on the floor, it started to spark and smoke. Fascinated, I clipped some little pieces
off of it and it sparked and smoked.......and then the end of it melted before my eyes!
What is it made of?
The wire is about 1/16th in thickness, there is no insulation and the wire is not
attached to anything. If I remember correctly, it came out of the microwave, ran
along the side and back into the microwave at another location. now keep in mind
that it was a built in so the sides were not finished like something you see on
the counter or above a cook top like a space saver. and it was maybe mid 1970's so
it was a very old microwave, maybe one of the first models. I cut it in half and
gave half to my sister's boyfriend who is a chemistry professor a S.P.S.C.C. and
have not heard back from him as of yet. The color is a dull silver with a slight
bronze tint. if you hold the wire in your hand and clip it a couple of times it
will spark.or the end will melt If you hit the end of it with a screw driver or
something, it will spark. If there is a way that I can send you a piece, I will be
happy to do so.
My first and most important recommendation is to terminate these experiments immediately.
From my "years of experience" with nasty substances, never do an experiment unless
you have a pretty good idea what the results will be. This is a safety issue.
Your microwave oven is leaking large amounts of microwave radiation. The electrons
in the from the microwave are inducing an oscillation of electrons in the metal wire.
They oscillate back and forth. However, in the process they encounter other atoms,
so there is a sort of microwave "friction". This very effectively heats the wire.
Relative to the energy input, the heat capacity of the isolated wires is small,
so the temperature increases even to the point of ignition and/or burning.
You are exposing yourself and others to microwave radiation.
FIND ANOTHER EXPERIMENT. THIS ONE IS POTENTIALLY VERY DANGEROUS.
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Update: June 2012