On 30/12/2018 01:27, Bob F wrote:
On 12/29/2018 3:20 PM, Harry Bloomfield wrote:
Dean Hoffman formulated on Saturday :
*Well,* the microwave cooking instructions on a lot of things say to
stir halfway
through cooking time.* That would lead me to think microwaves have
the same
issue as conventional ovens with the evenness factor.

I would expect the microwave energy to follow the inverse square law
and the energy to rapidly drop off the deeper it has to penetrate the
food, especially so if that food is a solid, with no convection
currents as in a liquid. So more power, will cook the outside too
quickly and leave the middle un-cooked or even cold.

Just like UHF TV has a harder time getting through rain, snow, trees and
walls than VHF.

That's why microwave ovens operate at 2.4GHz - the resonant
frequency/maximum absorption of energy in water molecules.