Via Built on Facts, it turns out that the cellphone-popping-the-popcorn movie was A FAKE! Gasp, thud. Making popcorn with a cellphone happens only in the movies.

(or should that be “only happens in the movies?”)

More than 6 million people have watched our little videos since May 28, 2008. We are very happy to have made this contribution to an important international public debate.

Important international public debate? Jane, you ignorant slut.

The teaser for the evening news just showed a clip of cellphones purportedly popping popcorn, and asking the question of whether it’s a hoax. My money’s on yes. Wired has a story on it, and there’s more than one video.

Assume a kernel has 0.1 g of water in it. You need to heat it from ~20 ºC to 100 ºC and then boil it, which is what happens when you pop popcorn. The heat capacity is 4.18 J/g, and the heat of vaporization is 2260 J/g. So this requires 80*4.18*0.1 +2260 * 0.1 = 260 Joules. This happens in a few seconds, so the absorbed power is somewhere around 50-100 Watts, per kernel. The transmitted power of the phones would have to be much, much larger, since it’s not focused on the popcorn.

Not.

Google also tells me that Zapperz beat me to the punch here.

Update: It looks like I overestimated the water content by a factor of about 5 (see link in comment 2; I assume medium-large kernels, though, not small. Orville has standards). Doesn’t change the overall answer. It takes my microwave oven ~3.5 minutes to pop my popcorn. A few hundred Watts for a (few) hundred kernels so let’s call it 1 Watt per kernel for 270-330 seconds (onset of popping is at about 2.5 minutes). That matches up pretty well with the numbers above, which we now know are overestimated. I see no reason to hypothesize that only infinitesimal boiling is happening.