Question

two sound wave originating from the same source, travel along different paths in air and then meet at a point. if the source vibrates at a frequency of 1KHz and one path is 83cm longer than the other, what will be the nature of interference? the speed of sound in air is 332m/s.

Answer 1

The wavelength is given as

λ = v / f

here,

v = velocity of wave = 332 m/s

f = frequency of wave = 10³ Hz

so,

λ = 332 / 10³

thus,

λ = 0.332 m

and

The phase difference between the two waves meeting at same point will be

δ = (2π/λ).dx

here

dx = path difference = 83 cm = 0.83 m

so,

δ = (2π / 0.332) x 0.83

thus,

δ = 5π

which is of the form

δ = (2n+1)λ.dx

and shows destructive interference.