(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What is the displacement amplitude of a sound wave of frequency 160.0 Hz in air at 20 °C at the pain-threshold pressure amplitude of 29.0 Pa?

f = 160 Hz

Vs = 343 m/s

ΔP = 29 Pa

2. Relevant equations

ΔP(x,t) = (ΔP)cos(kx - wt) = β*s*k*cos(kx - wt)

k = f/Vs

3. The attempt at a solution

ΔP = βsk

Therefore, s = ΔP/(β*k) = (ΔP*Vs)/(f*β)

β = 1.4 * 10^5 Pa

So the answer I got was 4.44*10^-4 m which is wrong. Am I missing something here?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Finding displacement amplitude given frequency and pressure

**Physics Forums | Science Articles, Homework Help, Discussion**