Belting Out A Musical Physics Lesson High school science teacher Sam Terfa wanted to demonstrate a fundamental physics principle: resonant frequency. To do so, he found the best singer at Minnehaha Academy and had him serenade a wine glass. It did not turn out well for the glass.
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Belting Out A Musical Physics Lesson

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Belting Out A Musical Physics Lesson

Belting Out A Musical Physics Lesson

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Time now for Flora Lichtman's Video Pick of the Week. Always looking forward to this, Flora, every week.


FLATOW: You got a good one this week, too, I know.

LICHTMAN: It is a good one this week, I think. So it's another science fair project for the recession.

(Soundbite of laughter)

FLATOW: On the cheap, in other words.

LICHTMAN: Yes, on the cheap. And that's mostly because there are not really that many materials involved. And it comes to us from the high school physics class of Sam Terfa.

FLATOW: Good old Sam.

LICHTMAN: Mr. Terfa is a physics teacher…

FLATOW: To me.

(Soundbite of laughter)

LICHTMAN: …yeah, at Minnehaha Academy in Minneapolis. And he is teaching resonant frequencies. And he knew that if you - that one illustration of resonant frequencies is sound shattering glass.

FLATOW: Those opera singers who could shatter, supposedly.

LICHTMAN: Well, that's the myth, right?

FLATOW: That's the myth, because you can't - yeah, right.

LICHTMAN: Right. So he started looking on YouTube, and then he was talking to his colleague about, you know, who might be - who at the school might be a good enough singer to attempt this.

FLATOW: Really?


FLATOW: And he cherry picked this kid who has won awards for singing, has this, you know, big operatic voice. And he said, you know, go home and just see if you can do this.

And he said that he got an email in the middle of the night that, you know, where this kid, David Morgan, is saying, Mr. Terfa, Mr. Terfa, I did it.


LICHTMAN: I shattered a wine glass by singing at it.

FLATOW: And so Mr. Terfa said, I had to see this, right?

LICHTMAN: That's right. So Mr.…

FLATOW: Not only do you see, he took videos of it that you have.

LICHTMAN: That's right. So actually, you know, we really make the most out of, like, a 10 second clip, truth be told.

(Soundbite of laughter)

FLATOW: But you see - I mean, if you go to Web site and you go to our Video Pick of the Week on the left, you will see him singing.

LICHTMAN: You see a high school student…

FLATOW: It's unbelievable.

LICHTMAN: …singing at a wine glass and it breaks in his hands.

FLATOW: Now, how do we know this is on the up and up, on the level, right? It could be a trick.

LICHTMAN: Well, actually, so we called another physicist, a guy at UCLA who does this demo for students with speakers. And he was like, you know, there is some controversy in the scientific community about whether you can actually do this with the human voice.

But, you know, we didn't do high-tech analysis, but I believe Mr. Terfa. And anyway, the point is really just to illustrate the concept that you can break glass with sound, which is well known.

FLATOW: That's amazing. I saw the demonstration. I saw when you put it together. I'm watching it on Video Pick of the Week. He sings into the glass and bing…


FLATOW: ...he has to get out of the way of the flying glass, doesn't he?

LICHTMAN: And the best part of the video I think is the kids in the background are going wild.

(Soundbite of laughter)

LICHTMAN: The crowds go wild.

FLATOW: There you have it, our Video Pick of the Week. Flora has got it up there. If you want to see how you can - and we have the only copy of this, I'll bet you, so far.

LICHTMAN: I think it's posted somewhere else, but it's little known…

FLATOW: Little known.

LICHTMAN: …I would say.

FLATOW: We're going to give publicity to the Video Pick of the Week of singing and breaking the glass, the wine glass. It's true. You can do it.

LICHTMAN: I think so. Thank you, Mr. Terfa.

FLATOW: Thank you, Flora. Flora Lichtman's Video Pick of the Week up there on Get there before everybody else does.

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