Flash Frozen Bananas and other mistakes

[Kerryl]

Just watched the Hamburger Postulate on reruns, and it struck me that when Leslie flash freezes her banana to break it in little pieces because she doesn't have a knife, shouldn't she wait until it thaws before eating it? Wouldn't it burn her mouth? I remember using dry ice for a haunted house in high school and we were cautioned not to touch it. Correct me if I am wrong. PS found another great Sheldon line....( to Leonard,) " Do you realize I might have to share a Nobel Prize with your booty call?" Anybody catch any other mistakes in this or other episodes?

[Monica]

just to hear sheldon say booty call cracks me up.

[Chris]

Actually it is the CO2 itself that you cannot touch as long as the banana doesn't have any frozen CO2 still on it you should be fine to eat it.

[Hoffi]

As bananas are primarily made out of water, their temperature in frozen state should be about 273 Kelvin. The small broken pieces have a huge surface,so that in an enviroment at room temperature (about 300 K) they heat up quite quickly from the temperature of liquid nitrogen (77K). So eating the banana pieces directly should be comparable to eating ice cream.

[Hoffi]

Right i checked the scene, the milk offers a big thermal bath. But i don't think this will be enough to thaw the banana really fast. Its a first order phase transition which will need a good amount of melting heat.

[Chris]

Leslie was eating cheerios she even said it and she is smashing the flash frozen banana because she couldn't find a knife.

[Chris]

Sorry

[Hoffi]

But the scene contains really an error. It's the safety goggles. I've never seen an experimental physicist wearing them and i've been to a few labs. Fortunately they don't wear lab coats, which would be the second and bigger mistake.

[Mike]

The symposium joke is a condensed bit of truth about the difference between technically and non technically trained people. I told the symposium joke to three of my usual lunch companions - 2 PhD's in physics and 1 PhD in physical chemistry - they all immediately laughed uproariously, as did I when I saw it. I'm sure no lay person could understand. Their metajoke is that we find the joke funny. Our metameta joke is that the joke actually is funny and they don't know it's funny.

[Kennedy]

I was wondering the same thing, but it was pointed out to me that the milk would raise the temp enough to not burn her mouth. Is this right?