university physicist

The Breakdown: Fast Freezing Beer

This little party trick is guaranteed to impress, and you don't need any special materials, just a decent freezer and a bottle of beer. Emory University physicist Sidney Perkowitz, the author of the forthcoming book Hollywood Science, says the phenomenon at work here is most likely supercooling - a process by which water can remain in a liquid state below its freezing point. It's a delicate balance, though, as the water will turn to ice given the slightest shock.

If supercooling is the culprit, the hidden scientist in this video most likely left the bottle in the freezer long enough for it to drop down below the freezing point - some other sites recommend about 30 minutes. Next, the shock of slamming the bottle on the table jolts the beer, and this added energy forces it to crystallize into ice.

Of course, it's hard to say for sure what's happening in this clip, and the many other frozen beer related videos posted on YouTube, because we don't have all the information. The best way to test the idea would be to try it yourself. I'd do the same, but I don't believe in waste.—Gregory Mone

Why do some sand castles stand firm until swallowed by the rising tide, while others fall over instantly?


Sand castles are ephemeral by natur—a good swift kick will destroy the sturdiest silicon-dioxide fortress in seconds—but scientists have learned that there are ways to maximize your creation's strength. Clark University physicist Arshad Kudrolli recently published a paper in the journal Nature Physics on just this topic, entitled"Maximum Angle of Stability of a Wet Granular Pile.â€

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Social Mathematics

The Company Geek

With each holiday season comes putrid pine-and-cinnamon-scented candles, hours fretting over gifts and, of course, the company Christmas party. One way to survive the fete is to sporadically emit esoteric mathematical factoids, which will encourage co-workers to either gather around and bask in your brilliance or scatter and let you swill drinks in peace.

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