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Hot Sausage 2

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kthree

Mechanical
Aug 9, 2004
57
Yesterday morning something happened that got me to a thinkin', and the subject matter is way outside my knowledge zone. See, I'm all gears and levers and such, but the issue in question contains current and invisiwaves. Whenever current is involved, my knowledge is pretty much limited to which speed-dial number connects to my electrician's cell phone. So, here goes. A normal morning startup for me is, pull the carafe out of the fridge, pour my cup full of left-over coffee, pop it and a sausage biscuit into the microwave and set it for 2 minutes. When the timer goes off, I take the coffee out, turn the biscuit over and nuke it for another 30-45 seconds, whatever my brain-on-morning-auto-pilot can manage to make my fingers select. That sequence always produces a cup of coffee that's just comfortably shy of too hot and a biscuit that contains just the right amount of sizzle. BUT, yesterday morning wasn't normal - There was no left over Coffee! That meant I was going to have to WAIT FOR MY COFFEE! Reeling from that revelation, I Grabbed a biscuit from the fridge, Stuffed it into the microwave, set the timer for 2 minutes and tried very hard not to break anything when I Punched start. As the familiar hum filled the background, I went about the normal resetting of the thermostat, turning the lights on, starting my computer, and checking the phone for a message light. As normal, I arrived back at the microwave as the timer went off. I reached in and grabbed the biscuit to turn it over… and stopped. It was warmer than normal. Was it my imagination? No, it really was more than 2 minutes warm. I understand why it takes a turkey longer to get hot in a microwave oven than an 8 oz cup of coffee, but the biscuit was the same size, composition, and density as always, it was rotating under the same wave generator as always, I had placed it offset from center about as much as I always do, but this time it got hotter than normal. When my microwave oven contains a sausage biscuit and a cup of coffee, does my cup of coffee somehow absorb microwaves away from the biscuit? All comments any wish to offer will be greatly appreciated. Thanks, K.
 
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In a regular thermal oven the whole shebang heats up. When you stuff something into it, 'it' soaks up some of the heat that is in the air and walls of the typically, already at-temperature, oven. Stuff two things or 4 things in and the heating rate difference, while present, isn't normally noticeable.

A microwave oven uses a completely different cooking mechanism. The magnetron microwave generator simply fills the microwave cavity with radio waves at a very specific frequency. They bounce around forever (in the life of a radio wave) until they're intercepted by something that absorbs them. Put more things in and there's more things sharing the interceptable waves. Water is what the frequency selected was aimed at heating. Put in water and it will take the lion's share of microwave energy.

Keith Cress
kcress -
 
Thank You itsmoked. That was very informative on several levels. Appreciate your help. K.
 
You bet!

You liked that? I'll offer more.

The heating process in a microwave oven is interesting. All molecules have multiple atoms stuck together to make them. If the resulting combination has odd angles between the combining atoms the compound will have polar charge. This means it will have a different charge when approached from a different angle. This 'polarity' means you can manipulate the molecule electromagnetically because the electromagnetic field has something to work against.

Water, H2O, is just such an compound. The two hydrogen atoms hang out next to each other on one side of the bigger Oxygen atom causing the polar affect. The engineers at Amana who came up with the first ovens (Amana Radar Ranges) chose the microwave frequency that would couple best with the polar water molecule to drive it. In a the microwave field in an oven the water molecules are furiously twisted back and forth around the polar center of gravity of the H2O molecules. This frictionally heats the surrounding atoms and molecules.

You may note that fats in a microwave seem to really get-with-the-program, and they do! But, part of the reason is because water takes waaaaaay more heat to heat up than lipids (fats) so fatty things actually heat up faster and a lot of fatty things have water in them too. Butter has lots of water in it but less mass and heats up shockingly fast in a microwave. Last week I had some Trader Joes butter explode in the microwave because it had lots of water absorbed into it and I came at it a bit too hard.

There you go, probably more than you wanted to know.

Keith Cress
kcress -
 
Just checked back for... Idon'tknowwhy, and WOW! Thank You. K.
 
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