Problem 20P

What would be the sound level (in dB) of a sound wave in air that corresponds to a displacement amplitude of vibrating air molecules of 0.13 mm at 300 Hz?

Solution 20PIntroductionThe process is isothermal, that is in this process the temperature remains constant. So we willuse the Boyle’s law of gas to calculate the final pressure of the gas. Now, since, the initialpressure is not given, first we will calculate the initial pressure using ideal gas equation.Solution:Step 1The ideal gas equation isWe know:n=0.10 molR=8.31 J/mol/KT=20°C=293 KV=50 cm =50 × 10 6 m3So the pressure is