1
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This place is really neat. Yeah, but I think we need to find Miss Leslie Bowie.

2
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Hi, I'm Leslie Bowie. I'm curator here at the Children's Museum of Virginia. How can I help you?

3
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Hi. Some of our dogs are barking and are waking us up at night.

4
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And we think that a really strange sound may be making them bark.

5
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Can you tell us what sound is?

6
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I think I can help you understand. Come over this way.

7
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Sound is created by vibration. A vibration is a back and forth motion, a lot like this slinky.

8
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An object vibrates and pushes air molecules around. Then these set other air molecules into motion.

9
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But we can't actually see the sound waves.

10
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But I can help you see the vibrations. This is a tuning fork. Listen.

11
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I can hear a sound. Me too.

12
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And I can help you see the vibrations.

13
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What is frequency?

14
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Frequency is the rate of vibration. The higher the frequency, the higher the pitch.

15
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Here, let me show you. I've flattened a straw and cut points. Now blow hard.

16
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I'll cut the straw.

17
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What do you notice?

18
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It's higher.

19
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I'll cut it again. What changes?

20
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It's even higher.

21
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It's kind of like these tubes. The longer the tube, the lower the sound.

22
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That's right. The shorter the tube, the higher the sound. It's a lot like this straw.

23
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Bianca, can you hear me?

24
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Yes, Kaylee. We're having so much fun. But now it's time to go.

25
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I don't want to go, but I'll go tell Mrs. Mooey thanks for the information.

26
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Okay. See you. Bye.