Answer:
10.0 m
Explanation:
Since there is no amplitude at the point of the swimmer, we have destructive interference.
So, the path difference ΔL = L₂ - L₁ where L₁ = swimmer's shorter distance from one generator = 9.0 m and L₂ = swimmer's longer distance from the other generator = 14.0 m. ΔL = 14.0 m - 9.0 m = 5.0 m
Also, since we have destructive interference, ΔL = (n + 1/2)λ where n = number of wavelengths and λ = wavelength of waves
For maximum wavelength, n = 0
So, ΔL = (n + 1/2)λ
ΔL = (0 + 1/2)λ
ΔL = λ/2
λ/2 = ΔL
λ = 2ΔL
λ = 2 × 5.0 m
λ = 10.0 m
So, the longest wavelength that will produce this interference pattern is λ = 10.0 m