Radio waves of very long wavelength can penetrate farther into seawater than those of shorter wavelength.....?
- oubaasLv 73 months ago
....the so called ELF message
wavelenght λ in air :
λ = c/(n*f) = 2.998*10^8 / (1*76) = 3,944,737 m (3.94*10^6 in exponential notation)
wavelenght λ' in water :
λ' = c/(n'*f) = 2.998*10^8 / (1.33*76) = 2,965,968 m (2.97*10^6 in exponential notation)
pic below from Crimson Tide movie
- Anonymous3 months ago
the navy uses the ELF ( extreme low frequency ) to communbicate with subs deep in the ocean .
- NCSLv 73 months ago
(a) λ = c / nf = 3e8m/s / 1.00*76Hz = 3.95e6 m
(b) λ = 3e8m/s / 1.33*76Hz = 2.97e6 m
near the very low end of the radio frequency range.