Δφ = 2πΔx/λ
where Δφ is the phase difference, Δx is the distance between the two points, and λ is the wavelength of the sound wave.
To find the wavelength, you can use the formula:
λ = v/f
where v is the speed of sound in the gas and f is the frequency of the sound wave.
Plugging in the values given in your question, we get:
λ = v/f = 320/400 = 0.8 m
Δφ = 2πΔx/λ = 2π(0.2)/0.8 = π/2
Therefore, the phase difference between the two points is π/2 radians.
λ = v/f
where v is the speed of sound in the gas and f is the frequency of the sound wave.
Plugging in the values given in your question, we get:
λ = v/f = 320/400 = 0.8 m
Δφ = 2πΔx/λ = 2π(0.2)/0.8 = π/2
Therefore, the phase difference between the two points is π/2 radians.