Monday, October 02, 2006

I don't understand the turntable

There are a lot of things that are puzzling about a microwave. I don't mean how they work, that's not that tricky. A filiment generating EM radiation about the same size of water molecules irradiates the food, vibrating the water to generate heat. What's so hard about that? Also, it doesn't cook from the inside out. That'd be absurd.

The thing that I have trouble with is the timer. I was heating up some stuffed shells for lunch today (they were delicious, by the way) and I accidentally hit 1 - 8 - 0 instead of 1 - 0 - 0 as I was trying to heat them up, when I realized, if I let this go, I have no idea for how long that will go. Will it be 180 seconds? Or 140 seconds, for a minute and 80 seconds? How come, when everything else in our society is base ten, our clocks and microwaves aren't? I also can't believe I actually changed it now, because I want to know how long it would have cooked for.

I also don't know why microwave manufacturers insist on putting in the turntable. Radiation, by nature, is emitted in all directions from its source, so reflections from the walls will cause the variety of angles sufficient to heat it from different directions. The turntable mostly makes my food spill and pulls off the paper towel I put on top to keep my food from spilling.

I also think it's pretty funny that people have discovered all sorts of weird things that will happen when you put crazy things into microwaves. Whoever the first guy was to put a cd into a microwave deserves a medal, because really, why would anyone ever think to do that? I think something crazy happens when you put a peep into microwave, too, but since I hate them I've never done it. I do, however, think it would be pretty fun to put a bottle of shaving cream into a microwave* and let it go for 3 - 6 -0, even though I have no idea how long that would be.

I have also decided that I never want to reheat pizza in a microwave ever again. It ruins the crust. So, really, there are only three options: take the time and reheat it in the oven, eat it cold or man up and finish it the day before.

*Please don't actually try this. I don't want to be responsible for internet kids getting burned by shaving shrapnel.

6 comments:

Anonymous said...

here is a fun trick, when placed in the microwave day old spaghetti turns into an inedible mush. TRY IT AT HOME!

Engineer Sighted said...

That sounds delicious, Drew.

Also, 1 - 8 - 0 leads to 140 seconds of microwave time, in case you were wondering.

Anonymous said...

I think that it actually is a rather difficult challenge to get the magnetron to disperse its output uniformly. I seem to recall reading that this is one of the challenges facing the designers of the first microwave ovens. They solved it by installing a rotating reflector in the top of the microwave. It is not visible to the user since the top is plastic. I always thought that a turn table was in addition to that, but after looking at my own today found that the top is metal so the turntable must be working on its own. From a technical standpoint I bet the rotating reflector is probably more effective and has the advantages of being easier to clean (since it is behind a smooth plastic cover) and not moving the food. However, since it isn’t visible the turntable a better selling point. In that sense, I agree with Brandon, the turntable is rather stupid.

Anonymous said...

If I remember correctly, the magnetron in most modern microwaves is in the side (not the top) and the other sides are designed to absorb the excess radiation.

So the turn table is necessary in order to get some uniformity in cooking.

Plus, I've used consumer microwaves without a turntable and there are usually many more "cold spots" in the food. The industrial microwaves without the turntables have bigger, better magnetrons, so sheer magnitude takes care of the turntable in that case.

Anonymous said...

Yeah, 1-8-0 would be one minute and eighty seconds.

What happens when you put a cd into the microwave?

And - "here is a fun trick, when placed in the microwave day old spaghetti turns into an inedible mush. TRY IT AT HOME!"

Ha ha ha ha.

Engineer Sighted said...

I didn't realize that microwaves were the magic subject to get people to leave lengthy comments. Maybe I'll leave technically ambiguous claims in the future to try to get engineers to argue about it...