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Posted

You know its the off season when....

 

Dear Straight Dope:

I have a question that neither of my high school science teachers could answer for sure, including my physics teacher, who scored 1590 on his SATs (he also found an error on the test) and is a member of Mensa. If I were to put liquid nitrogen in my microwave, what would happen? Would it superheat and instantly explode or would it just boil off like if it was in regular air? By the way, my teacher suggested for me to try this experiment. 

 Ryan Deckard, Indianapolis, Indiana

Chronos replies:

SDSTAFF Alphaene replies:

Here at work I am within three feet of both a microwave and 240 liters of liquid nitrogen. However, even if I leave my job I’d like my boss to be a reference. And if he said “everything was fine until he superheated liquid nitrogen and destroyed the lab microwave," it may not reflect positively on me.

SDSTAFF Chronos replies:

When I saw this question, I was going to answer based on the resonance properties of water and nitrogen molecules. Microwaves work by exciting resonances in water molecules, and the water, once excited, heats up everything else in the frozen dinner you’re cooking. Since water is an asymmetric triatomic molecule, it has three distinct rotational modes and three more vibrational modes, making it easy to find resonances. Nitrogen, on the other hand, is a symmetric diatomic molecule, so it only has one distinct rotational mode and one vibrational mode. That makes it much harder to match a resonance for nitrogen, so the microwave probably wouldn’t do anything to it.

That’s how I was going to answer. But that’s boring. Here at the Straight Dope, we do experiments.

I went to the instructional lab supervisor here and asked if I could have some liquid nitrogen for, uh, “instructional purposes." Having obtained the substance, I then proceeded to pour equal quantities into two identical paper cups. One was left outside as a control, and the other was placed in the microwave, which was set for one minute.

It turns out that my prediction was half-correct. Liquid nitrogen is, as I suspected, transparent to microwave radiation. The effect of this transparency, however, is not that “nothing happens." The effect is the same as when a microwave oven is run containing only air: a spectacular light show of sparks and flashes. Although my view of this phenomenon was somewhat hindered by the skull-and-crossbones sign on the door of the microwave, I decided that it would be nonetheless prudent to cut short the experiment after approximately one second. Afterward the liquid level in both cups remained the same, to within the limits of measurement. When an empty cup of the same sort was placed in the oven, similar pyrotechnics were produced. We may therefore conclude that, so far as the microwave oven is concerned, liquid nitrogen behaves in the same way as the atmospheric nitrogen normally present in the cooking chamber. 

Later it occurred to me that there was no reason to halt the experiment prematurely.  A cup of liquid nitrogen would hardly be expected to catch fire, so the only concern would be damage to the magnetron tube. Since the next experiment proposed for this microwave was, “What happens to a microwave oven dropped from the ninth story?" the fate of the tube was likewise not an issue. Unfortunately, this thought did not occur to me until after my office-mates had already scattered the liquid nitrogen on the floor to see the Leidenfrost effect, so further tests were impossible.

 Chronos

Send questions to Cecil via [email protected].

STAFF REPORTS ARE WRITTEN BY THE STRAIGHT DOPE SCIENCE ADVISORY BOARD, CECIL'S ONLINE AUXILIARY. THOUGH THE SDSAB DOES ITS BEST, THESE COLUMNS ARE EDITED BY ED ZOTTI, NOT CECIL, SO ACCURACYWISE YOU'D BETTER KEEP YOUR FINGERS CROSSED.

 

Posted (edited)
16 minutes ago, Radar501 said:

Did you know she was a dipstick......and couldn't park......and was a god dam moron.......and dead stupid......who couldn't be trusted to load your dishwasher.......and whose food you wouldn't eat

 

BEFORE SHE BECAME YOUR WIFE?

nice one.... <deleted> ?

sorry deleted. I meant to say what on earth are you on about you crazy sober cobber.

Edited by jastheace
Posted
2 hours ago, AlexRRR said:

Its Draft day.........Xmas in November......we have all these special AFL days....quick throw hat into the ring, some would say Eagles all ready had there draft, sold there soul to the devil for one Kelly....as did the Demons last 2 years in a row and what did they get? a big hospital bill instead...

 

For the footy addicts here and you know who you are....bit like speed....or todays drug of choice Ice...gets ya high, feel invincible living the dream until your coming on down and back into the hole that is real life...

 

Who was the first ever number 1 draft choice and what team did he go to?

 

Can you answer that without googling?

 

Tonight spread out over several so that it seems kinda special yet it aint cause the AFL are kind slow to come up with a formula that works like x I remind you of X and how it died a death and lets not forget the Suns playing in China...seems kinda fruitless to me when Chinese clubs backed by the government were prepared to throw a Million big ones PER WEEK at Garth Bale to play in China last year, even a primary school drop out from Brodie would see that Aussie Rules wont ever be anything over there....maybe HK is where they should be setting it up they can battle it out with the protestors....or the Phillipines..over 100 million people there...

 

 

The draft never really does it for me TBH.

 

Just about every kid is rated as an elite kick, mark, runner etc etc.

You should get a decent player in the top 10 I reckon, but it's still a

bit of a lottery.

  • Like 2
Posted
16 minutes ago, Radar501 said:

The fella who lives up the road hangs his washing out each Friday morning.   Every time he pegs the same items in the same spot, including five old pairs of footy socks.

 

Doctor assures me that my interest in the neighbour's laundry should be no cause for concern.

 

 

DSC00030 (2).jpg

At least while you've still got your electronic ankle bracelet on.

  • Like 1
  • Haha 1
Posted
4 hours ago, Radar501 said:

The fella who lives up the road hangs his washing out each Friday morning.   Every time he pegs the same items in the same spot, including five old pairs of footy socks.

 

Doctor assures me that my interest in the neighbour's laundry should be no cause for concern.

 

 

DSC00030 (2).jpg

Think you might be a bit kinky there old Radar....

  • Haha 2
Posted

Ps...Good guys refunded me $170 at 11.30 and at 12.30 i purcesed a pair of Nike....20% off (Black friday you know....) for $160 which left me with $10, almost covered the cost of my lunch at $12......

 

Dont forget Luke jackson WILL.......he WILL be getting home sick in 3 to 4 ys time.....start saving them first round draft pics mate...

  • Like 1
Posted
58 minutes ago, Radar501 said:

Reckon when LX flew to Thailand last, he could have answered FJ's urgent SOS call for a pie-maker.   Poor lad must have been getting withdrawal symptoms for a nice dog's eye drowned in dead horse.   Only a fair dinkum Aussie would understand that slang.

 

I love Thai grub, but I agree that their bread-making skills are appalling.   If you wanna sample the very best bakeries in SE Asia, you need to be in Laos, Cambodia or Vietnam.   The locals never liked being under colonial rule, but at least the French taught them how to use dough in their cooking.

 

EDIT:   Just saw your post above Will.   Why don't you get Bookman to pop his head onto the footy forum and say g'day.

Books might rejoin the tipping next year...hes been having withdrawal and peed off i came second this year im sure he thinks hes better than me... as for the pie maker i bought the kmart job to actualy do some thai spicky chicken balls in it of course ive deep fired them instead as washing the dam thing takes longer than cooking....

 

That might be a new business idea for uncle WILL....4n20 would sell pretty well there im sure....dont forget the tomato sauce....not tomato pasta sauce or ketchup....good old tomato sauce....yanks in here once missunderstod me over that..

  • Like 2

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