Amateur Extra › E9 Antennas and Transmission Lines › E9F03
E9F03
Why is the electrical length of a coaxial cable longer than its physical length?
Pick an answer to check it.
Answer: D. Electromagnetic waves move more slowly in a coaxial cable than in air
Waves move more slowly in coax than in air, so more wavelengths fit in a given length. Electrically the cable is longer than it physically is.
Tip: Slower in coax, so electrically longer.