D
Danny
- Jan 1, 1970
- 0
Hi
What is it that causes the sparks when you put something metalic into a
microwave oven?
Danny
What is it that causes the sparks when you put something metalic into a
microwave oven?
Danny
Danny said:Hi
What is it that causes the sparks when you put something metalic into a
microwave oven?
Danny said:Hi
What is it that causes the sparks when you put something metalic into a
microwave oven?
Danny
Hi
What is it that causes the sparks when you put something metalic into a
microwave oven?
Danny
Hi
What is it that causes the sparks when you put something metalic into a
microwave oven?
Standing waves bouncing back and forth along conductors produce large
voltages at the ends of the sections if the length is an odd multiple
of a half wavelength and at all have wavelength points. Put this
conductor in a nearly closed loop and those high voltages are opposite
polarity and large enough to arc across the gap. Sheets of metal
seldom arc, unless they are so thin that the RF currents burn them
into small pieces (like the foil layer in a CD).
Paul said:I often put my teacup in the mw to warm it up. I leave a teaspoon in
it too and don't get any sparks. OTOH, if I use a teacup with a
guilded edging, I get an indoor thunderstorm. Seems to back up your
findings.
If you look at the burnt gilding, you will find that it is broken into
similar length pieces of about 1/2 wavelength, each.
Paul said:Even if the turntable is rotating during the nuking?
John said:If you look at the burnt gilding, you will find that it is broken into
similar length pieces of about 1/2 wavelength, each.
Clifford said:Funny. I coulda sworn that 2.xGHz had a wavelength in the vicinity of five
inches. Most teacups are about half a wavelength *across*, but the gilding
breaks up into pieces 1cm or less. Guess you don't need a half-wave to
get heating, huh...
Others have answered your query, I'll just add a bit of trivia: It doesn't
have to be metallic: try diced raw carrots some time.
Is this because carrots are metallic?
Seriously, why do carrots do this?
John Woodgate said:I read in sci.electronics.design that N. Thornton wrote:
Yes; the colour is due to the high concentration of orangeonium.
Water content.
Probably. I believe you can get courgettes to light up on US 120 V mainswrote (in said:Right, but other veges also have water content and arent prone to
arcing the way carrots are. I think I know the answer here: guessing
time: the carrot I expect has less water content than many other
veges, and has a low enough content to encourage standing waves, but a
high enough content to remain electrically conductive - thus creating
the 2 requirements for arcing.
John Woodgate said:Probably. I believe you can get courgettes to light up on US 120 V mains
because they have a high enough cue. (;-)