Waves, Oscillations & Acoustics
5 terms
Absorption Coefficient
Waves, Oscillations & Acoustics
Dimensionless
The fraction of incident sound energy absorbed by a material surface rather than reflected.
α = I_absorbed / I_incident (0 ≤ α ≤ 1)
Acoustic Impedance
Waves, Oscillations & Acoustics
Pa·s/m (Rayls)
The physical opposition offered by a medium to sound wave flow, defined as ratio of acoustic pressure to particle velocity.
Z = ρ v_sound
Acoustic Power
Waves, Oscillations & Acoustics
W
The total sound energy emitted by an acoustic source per unit time in all directions.
P_ac = ∫ I · dA = 4π r² I
Acoustic Resonance
Waves, Oscillations & Acoustics
Hz
The amplification of sound waves within a hollow cavity or tube when driven at frequencies matching cavity standing wave modes.
f_n = n v / (2 L)
Angular Frequency
Waves, Oscillations & Acoustics
rad/s
A scalar measure of rotation or oscillation rate expressed in radians per unit time.
ω = 2π f = 2π / T