For sound waves in air with frequency 1000 Hz, a displacement amplitude of 1.2×10−8 m produces a pressure amplitude of 3.0×10−2 Pa. What is the wavelength of these waves? (Provided Bulk modulus of Air = 1.42× 105Pa)
0.36 m
Given f=1000 Hz, A0=1.2×10−8m
ΔP0=3×10−2Pa
WE known ΔP0=BA0K
⇒ ΔP0=B.A0.(2πλ)
λ=B.A02πΔP
=1.42×105×1.2×10−8×2π3×10−2
=0.36m