Formulas
September 7, 2021
2:34 PM
Simple Harmonic Motion / Springs
Sound Waves (Longitudinal)
Images and Stuff
Air density:
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Speed of sound:
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Threshold of hearing:
Threshold of pain:
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- distance between relaxed position and
equilibrium position
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○ Phase = stuff inside trig function (
)
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Pressure change
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Intensity (unattenuated)
Potential energy of a spring
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Simple Pendulums
- area perpendicular to wave
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Geometric spread
If θ is small (under 15°, sin(θ) ≈ θ):
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Waves
- dimension (1D, 2D, or 3D)
Sound level
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Wave Interference for same , , and
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- dimension (1D, 2D, or 3D)
- attuenuation coefficient
Attenuation
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- difference in phase angle between
component waves
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- attuenuation coefficient
Combined spreading and attenuation
Waves on Strings (Transverse)
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Acoustic Impedance
- Linear density in
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Sound Waves in a Fluid
- tension in string
Impedance
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- speed of the longitudinal wave
- bulk modulus of fluid (resistance to
compression in
or )
○ - density of fluid
Power
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Amplitude reflection coefficient
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Sound Waves in a Solid
Amplitude transmission coefficient
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Power reflection coefficient
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Power transmission coefficient
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Standing Waves
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- harmonic number
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- distance between
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nodes
Waves in an Ideal Gas
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- ratio of heat capacities
- gas constant (
- absolute temperature in
- molar mass
)
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Notes Page 1
- speed of a longitudinal wave
- elastic modulus (stiffness in
- density of rod material
or
)