Answer:
distance between two points having phase difference 5.6 rad is
Φ = 2.33 m
Step-by-step explanation:
given
frequency, f = 130Hz
speed of sound in air, v = 340m/s
distance between two crust or through with phase difference 2
= λ (wavelength)
phase difference = 5.6 rad
note: distance between two points having a phase difference =

∴ distance between two points having phase difference of 5.6 rad is =
×5.6
Recall
v = f × λ
speed = frequency × wavelength
wavelength = speed/frequency
λ = v/f
λ = 340/130 = 2.615 m
∴ distance between two points having phase difference 5.6 rad is =
×5.6 = 2.33 m