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since the Christmas season is here, I would like to ask a question about the movie, "A Christmas Story." In one of the subplots of the movie, Ralphie's friends were betting each other that their tongue would stick to to a frozen pole. Finally, the kid did it and it stuck to the pole.

Why does this happen? I believe that there is a physics explanation for this.

DanielSank
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TanMath
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1 Answers1

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The reason is the same as why a metal pipe feels colder than wooden plank at the same temperature: thermal conduction.

The heat from your tongue (including the moisture) is absorbed faster than your body can replenish it. This has the effect of freezing your saliva in the tongue's pores to the metal surface (which itself isn't too smooth at small scales). Doing that will net you this:
enter image description here

The remedy is actually quite simple: get some warm water and pour it where your tongue is stuck and you'll be free.

Kyle Kanos
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    Pressing the tongue onto the metal pipe should help too. I haven't tried it though. – pfnuesel Dec 16 '14 at 19:23
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    @pfnuesel: Hmm, I'm not sure why that would work. Seems to me that it'd just increase the frozen surface area, leading to being stuck even closer. – Kyle Kanos Dec 16 '14 at 19:24
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    Maybe go in for the full-on smooch - the pole may... 'warm up to you' ;D – Danu Dec 16 '14 at 19:38
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    @KyleKanos Because higher pressure will always liquefy water. It's not cold enough to try it here, though. (I'm basically advocating this solution as an alternative to getting warm water, since it may not be easy to get warm water when your tongue sticks to a pole.) – pfnuesel Dec 16 '14 at 19:45
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    @pfnuesel that's just an misconception. The ice-liquid saturation line (p-T diagram) is practically vertical. Also, even if it's doable, the pressure would have to be HUGE. Also, higher pressure will definitely not ALWAYS liquify water. There's a very clear limit: 251 K (-22 °C). See http://goo.gl/Vuq6hT. – André Chalella Dec 16 '14 at 20:55
  • @pfnuesel - Most people have a ready supply of warm liquid that can work to get you unstuck, as this urban legend shows, though I doubt that many people would want to have to resort to urine to free their tongue. – Johnny Dec 16 '14 at 21:48
  • @AndréNeves Maybe pressing your tongue leads to you putting lots of spit on the contact area and that is enough warm liquid to unstick it...? – Brad Dec 16 '14 at 22:33
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    @pfnuesel I triple dog dare you. – LarsTech Dec 16 '14 at 23:56
  • @Brad well, spit is what got you stuck in the first place! – André Chalella Dec 17 '14 at 13:10