When I received two almost identical video clips from a friend, of a group of friends using their cellphones to make popcorn, my first thought was “Oh wow! Didn’t know that would work!”
Fortunately, a healthy dose of scepticism kicked in before I clicked the ‘Forward’ button!
The one clip showed three French-speaking friends sitting around a table, and the other showed four Chinese ones (I think). They placed four cellphones in a circle, a couple of kernels of unpopped popcorn in the middle, and then used another four cellphones to call the four phones on the table, which started ringing and/or vibrating. A few moments later, the corn kernels popped! Much cheering and jubilation followed.
As I was watching the clips again, a third year vacation project student in Electrical Engineering came into my office to ask me a question. He watched the clips with me, intrigued, before declaring confidently, “No, that’s not possible. There’s got to be a heat source under the table.”
Turns out he was right! A bit more searching on the web led me to the video-clip on this website, which demonstrates how this little parlour trick was (probably) done.
An article on Blog.Wired.Com with the title “Physicist Debunks Cellphone Popcorn Viral Videos” quotes a physics professor at the University of Virginia. Prof Louis Bloomfield actually does exist (such things cannot always be taken for granted on the www), and in fact he has written a book with the compelling title How Everything Works: Making Physics out of the Ordinary (Wiley, 2008).
To quote from the article:
“In a microwave oven, energy excites the water inside popcorn kernels until it turns into highly pressurized gas, causing the kernels to pop. If mobile phones emitted that much energy, the water in the fingers of people holding them would heat up.
“It would hurt like crazy,” Bloomfield said. “Cellphones probably warm your tissues, but studies indicate that’s not injurious.”
Bloomfield, author of How Everything Works: Making Physics Out of the Ordinary, dismissed theories bubbling up in comment threads about the videos that suggest harmonious vibrations are heating the corn.
“Ringing the phones doesn’t help because they’re interfering with each other and receiving a signal [from a cellphone tower] — not transmitting it,” he said. Furthermore, while it is possible to heat with sound, it’s not likely to happen at the low volume emitted by a mobile phone. “It would be like gathering opera singers together to sing, and trying to make the corn pop,” Bloomfield said.
So, what’s really causing the kernels to ricochet off the table in the YouTube clips? Bloomfield suggests tricky video editing or even a covert heating element beneath the table.”
According to an article in PC World called “The Great Popcorn Hoax”, this was a viral marketing campaign conducted by a company called Cardo Systems:
Cardo Systems, a manufacturer of Bluetooth headsets, recently claimed responsibility. The videos were produced by LastFools, a marketing firm in Paris. I asked one of the video’s creators, LastFools’ Frederic Chast, what editing program he used. “Your question is biased because you work at a PC magazine,” he said. “Maybe if you worked at a kitchen mag, you’d ask me what heating plate I used.”
Cardo Systems seems to say that if you were dumb enough to grab some friends and try to pop corn with your cell phone, and it didn’t work, don’t blame–or sue–us: “The contents of these videos are fictitious and humorous optical illusions, designed for entertainment. Nothing in these videos is meant to imply that mobile phones can make popcorn and Cardo Systems specifically disclaims that these videos contain any portrayal of facts or comments about safety. Cardo disclaims any liability for the information in these videos.”
I’m not entirely sure what the point of this campaign was – Apparently the purpose is to sell wireless Bluetooth headsets. But I wonder how many watched the video clips and went ‘oh, that sounds correct’, instead of checking out the various hoax buster websites (like Snopes and Virus Hoax Busters).
Because if you didn’t, and if you do believe that cellphones emit invisible electromagnetic radiation that is powerful enough to pop popcorn, then surely you would be quite reluctant to hold a cellphone near your ear – or for that matter, to clip a little wireless gadget to your ear. Or am I missing something?
Please excuse me, I’ve got some studying to do.