Problem 12.25 Challenge

กำหนดให้ \(f = 1,000 Hz, I = 1.00\times 10^{-12} W/m^{2}, ρ = 1.29 kg/m^{3}\)

และ \(v = 343 m/s\)

จาก \(I = \frac{\wp}{A}=\frac{1}{A}(\frac{1}{2}ρA\omega ^{2}s_{\max}^{2}v)=\frac{1}{2}ρ(2\pi f)^{2}s_{\max}^{2}v\)

\(\therefore s_{\max}=\frac{1}{\pi f}\sqrt{\frac{I}{2ρv}}= 10.7\times 10^{-12} m \;\blacksquare\)

จาก \(\Delta P_{\max}= kρv^{2}s_{\max}=(\frac{\omega}{v})ρv^{2}s_{\max}= (2\pi f)ρvs_{\max}\)

\(\therefore \Delta P_{\max}= 2.97\times 10^{-5} Pa \;\blacksquare\)