Red Light, Green Light

Oct 15, 2007

RAY: This is from my traffic signal series. Truth be known there was only one puzzler in the series, 'til today that is!

You may recall the other traffic signal puzzler was about these new LED traffic lights that seem to be popping up just about everywhere. And well they should; they're fabulous.

#1. They hardly ever burn out. And because every light consists of dozens of those little diodes, even if some of them do burn out, the light still works, unlike the old incandescent bulbs, which burn out and leave you with no signal whatsoever.

More than that they use a small fraction of the energy of the old incandescent bulbs.

And #3. They're brighter! So win, win, win, right? Wow, this is great! Now, of course, it costs quite a bit to purchase and install these lights, but in the long run they're worth it.

However, as magnificent and wondrous and splendid as these LED lights are, they do have one disturbing shortcoming -- one flaw, one defect, if you will. What could it be?

Now before you go off the deep end, I'm going to give a hint. If I had waited a few more months before using this puzzler some of our listeners might have found it a little too easy.
RAY: The hint I gave was if I had used this puzzler a few months from now, the flaw might be much more obvious. Now do you know the answer?

TOM: Ohh, a few months from now I'm going to guess that would have brought us to winter.

RAY: Yes.

TOM: And in some parts of the country it gets cold and snowy.

RAY: And because these lights use so little energy they emit no heat.

TOM: Yeah.

RAY: And when wind blows snow and sleet and whatnot --

TOM: It stays right there. It doesn't melt it.

RAY: Exactly. And the old incandescent lights used to melt the snow. In fact, I talked to the chief traffic guru in Our Fair City of Cambridge, Jeff Morenti, and he said, oh yeah, this is a problem that nobody foresaw.

TOM: Of course. That's why we shouldn't live around here. Just another reason.

RAY: So who's our winner?

TOM: The winner this week is Alma Blum, from Palmer, Alaska.

RAY: Oh, Alma, Alma you're going to need a prize.

TOM: And for having her answer selected at random from among all the correct answers that we got, Alma is going to get a 26-dollar gift certificate to the Shameless Commerce Division at, with which she can get our new CD collection called, Four Perfectly Good Hours. Congratulations Alma for being this week's puzzler winner.

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