Re: superheated drink (was: How to explain this?)

[Larry Cartwright <exit60@CABLESPEED.COM>]

"John S. Denker" wrote:
> To fully explain Ludwik's report, one has to imagine
> that some of the liquid was superheated but some of
> it wasn't.

This tendency is suggested by experimental evidence.  Take a chunk (a US
non-metric unit of mass) of frozen hamburger and nuke it in your
microwave.  You will find that various portions of the burger are in
different states, here thawed, there still frozen, and some portions
cooked.

This tendency coupled with the poor thermal conductivity of most liquids
should tend to produce *pockets* of superheating.

I believe this doesn't usually happen when liquids are heated on the
stovetop because heating from the bottom sets up convection currents,
which provide mixing that prevents hotspot pockets from forming.  An
interesting (to me) gedanken:  what do you think would happen if were to
heat a liquid on a stovetop with a flame *so intense* that it heats the
water in the bottom of the pot to boiling before convection has an
opportunity to set in?

Best wishes,

Larry

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Larry Cartwright     <exit60@cablespeed.com>
Retired Physics Teacher
Charlotte MI 48813 USA
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Lord, preserve us from the excesses of those
who would do us harm; and preserve us from
the excesses of those who would protect us.
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