"decaturtxcowboy" <nope_none_@nowayspam.com> wrote in message
news:O8toh.11976$ZT3.10342@newssvr19.news.prodigy. com...
> miso@sushi.com wrote:
> > Isn't there some magic relationship between H2O and 2400Mhz? Like water
> > absorbs the 2.4G RF most efficiently, and thus microwave ovens use this
> > frequency.
> >
> > Wifi isn't all that far away in frequency.
>
> Actually that's urban myth. Microwave ovens use 2.4 GHz because its in the
> unlicensed ISM band.

Microwave ovens were using 2.4Ghz way before people jumped on the 2.4Ghz for
unlicensed radio use. In fact microwave ovens were already listed as being
potential interferers to 2.4Ghz radios.
http://www.zyra.org.uk/microw.htm
Food has a high percentage of water, and water is famously H2O. The molecule
of water has the O (Oxygen) in the middle, and the two H's (Hydrogen) stuck
on it like Mickey Mouse ears at a particular angle (105o). The H's are
positive and the O is negative, so the molecule has a + and - end. It has
"polarity".
Polarised molecules try to line themselves up with the electrical field,
like compass needles trying to point at North.
But because the electrical field is changing 2,450 million times a second
the molecules don't quite have time to line up one way before they have to
try to line up the other way!
So, anything with water in it has all these molecules being moved this way
and that by the electrical field, and heated up.

http://www.ccohs.ca/oshanswers/phys_...ave_ovens.html

The microwave radiation produces heat inside the food in the oven. Heat is
produced when the water molecules in the food vibrate (at a rate of
2,450,000,000 times per second) when the food absorbs the microwave
radiation. The movement of the molecules produce friction which causes heat.
This heat cooks or warms up the food.