Originally posted by Ace Of Bass
I don't think dry towels microwave well. Only polar molecures (like water and triglycerides) absorb the radiation, and heat up because the oscillating waves cause the polar molecules to turn on their axis to follow the waveform.
I don't think cotton is polar.
Microwave ovens are specifically tuned to excite water molecules the best. So, liquid molecules with similar properties, especially if they're mixed with water, are the best stuff to heat. Most cooking oils will overheat in some areas and not heat enough in others. Which is why they may burn while not cooking. Dry goods don't seem to heat well, period.
Microwaves heat by vibrating the molecules to build the energy in the molecules, to thereby raise the internal heat level, thereby raising the temperature. Normal ovens use higher temperature to drive heat in to the molecules, to thereby raise the internal energy of the molecules, which then raises the temperature. Basically, they're nearly reverse procedures. The key is that kitchen microwaves are tuned to a good avaerage frequency for forcing water and water-bases fluids to boil. (Which is also why some things like popcorn are hit'n'miss. ) It could just as easily be tuned better for neon gas to glow, or crude oil to thin, or brine, or...