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Name: Daniel 
Status: other 
Grade: other 
Location: WA 
Country: USA
Date: Winter 2009-2010



Question:
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.


Replies:
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.

Vince Calder



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