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11.6 Resonance Matching an object’s natural frequency

with an external force

Since most objects have elastic properties, resonance can cause them to be damaged or destroyed.

Breaking a glass with sound Tacoma Narrows Bridge Bridge in Russia

mkf

21

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11.7 Wave Motion Oscillations that move through matter

and carry energy.

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11.7 Wave Motion

Wave speed

For a string:

fv

LmFv T

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11.8 Types of Waves Transverse and Longitudinal

Example 1

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11.8 Types of Waves Earthquakes and Water

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11.9 Energy Transported by Waves

2

21 kAE

24/

rpower

areatimeenergyI

1

2

1

22 I

rrI

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11.11 Reflection and Transmission of Waves

Newton’s 3rd Law

Similar to a wave travelingfrom water into oil

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11.12 Principle of Superposition Constructive and destructive

interference In phase or out of phase?

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11.13 Standing Waves Due to the

superposition of the waves at certain frequencies

Fundamental Frequency

Overtones or Harmonics ... 3, 2, 1, 2 1 nnfLnvfn

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In class: Problems 54, 82 Other problems ↓

TFvm L

28 m 0.35 s

150 N0.65 kg 28 m

T

T

Fx xv t

t m L Fm L

41. To find the time for a pulse to travel from one end of the cord to the other, the velocity of the pulse on the cord must be known. For a cord under tension, we have

.