The U. S. Navy has long proposed the construction of extremely low frequency (ELF waves) communications systems; such waves could penetrate the oceans to reach distant submarines. Calculate the length of a quarter-wavelength antenna for a transmitter generating ELF waves of frequency 77 Hz.
Answers: 3
m/s
→ wavelength of the antenna
→  speed of light
from
= 
m
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The U. S. Navy has long proposed the construction of extremely low frequency (ELF waves) communicati...
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