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Physics of Waves

What is sound?

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Physics of Sound

I. Basics of soundTerms and word wall

II. What is a wave?III. Ultrasound

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Sound word wall

• Wave• Crest• Trough• Amplitude• Frequency• Hertz• Pitch• Doppler effect• Noise

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What is a wave?

http://www.fearofphysics.com/Sound/dist.html

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What is a wave?

1. The wavelength of the wave in the diagram above is given by letter ______. 2. The amplitude of the wave in the diagram above is given by letter _____.

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What is a wave?

3. Indicate the interval that represents one full wavelength.

http://www.fearofphysics.com/Sound/dist.html

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Waves

• What is sound?– Pitch– Frequency– Noise

• What is noise?– How do noise differ from sound?

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Ultrasound

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Ultrasound

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UltrasoundUltrasound imaging: imaging the heart

heart valves

atrium

ventricle

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UltrasoundUltrasound imaging: carotid artery

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UltrasoundUltrasound imaging: carotid artery

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UltrasoundUltrasound imaging: carotid artery

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• Speed = Wavelength • Frequency• Using the symbols v, , and f, the equation can

be rewritten as• v = f •