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This week, Collected Wisdom was about to relax and turn on the radio, but it appears that there is no need. We already seem to be picking up Jian Ghomeshi on our molars.

The question

Can people really pick up radio waves on their teeth braces or fillings? Jackie Phillips of Toronto wants to know.

The answer

Indeed they can, says David Guy of Halifax. "In the mid-1970s when I was a student at Carleton University," he writes, "there was a girl who got 580 CFRA radio on her braces" at one spot on a lane leading to the residence buildings.

"It became a running joke as we walked to and from class because you could count on it. It came in so clearly that bystanders … could play Name That Tune."

That would be thigh-slappingly mirthful for the bystanders, CW would think, although not so much for the human radio.

But how does this strange phenomenon occur? Coming through loud and clear on this is Bill Gade, regulatory affairs officer for Radio Amateurs of Canada, an organization of radio enthusiasts based in Ottawa.

Consider the humble crystal radio, he says. It has no batteries, but it can pick up radio signals through a grounded wire antenna. To put it simply, it works by electricity being able to flow through the radio in one direction and not the other. That same one-way flow can make your braces or a filling vibrate in sync with music on the radio. If the signal is good enough, Mr. Gade says, you can clearly hear the song.

"This can happen when two metal objects are very close but not totally touching, like a cracked or loose filling or the wires of your braces."

The closer you are to a large AM transmitter, the more likely you are to hear music in your mouth. (You won't pick up an FM station because of the different type of signal.)

"When AM transmitters were common in big cities," he writes, "it was an everyday occurrence for people living near them to hear the station on their toasters, from their light bulbs and even from things like a metal spoon resting in a metal cup."

If you're picking up a certain station a lot on your teeth, he says, your dentist can change the size of the filling or the length of wire in your braces to solve the problem.

"The change in size or length will effectively 'tune' you to a different station."

The question

"If you had only one type of food for the rest of your life," write Greg Pinks and his daughter Nicole of Guelph, Ont., "what food would keep you alive the longest?"

The answer

We haven't received any definitive answers on this yet, but John Cameron of Toronto says you could do a lot worse than eat plenty of honey.

"Honey does not require refrigeration and never rots," he writes, "and most harmful bacteria cannot live in honey for any length of time."

He points out that the ancient Greek philosopher Democritus chose a diet rich in honey and lived for 90 years.

Help wanted

When a boxer is knocked out, has he suffered a concussion? asks George Cuthbertson of Burlington, Ont.

Why are the bottoms of cargo-ship hulls painted a copper colour? Peter Simpson of Toronto wants to know.

Judy Cameron of Ottawa asks: How do cows and horses survive outside in an Ontario winter?

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