1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL)

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1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL), astronomy, astrophysics, cosmology, general relativity, quantum mechanics, physics, university degree, lecture notes, physical sciences

Transcript of 1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL)

Page 1: 1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL)

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k2 π.

10 a.

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k2 π.

6 a.

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Page 2: 1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL)

k2 π.

2 a.

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Page 3: 1B24 Waves Optics and Acoustics Lecture 8 of 33 (UCL)

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Derivation of Equation of Motion for String under Tension

An element of length ds (approximately equal to dx) is acted upon by the tension T at an angle θ at x and θ+dθ at x+dx.

Displacementy

T

T

x x+dx

Str ing element length ds

θ

θ+dθ

1

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