This is a follow-up to N4HNH's excellent video on Basic Antenna Theory. It is meant to go deeper to dig into the basic concepts that N4HNH has brought forward.
It also attempts to answer the question of why the 50 ohm standard for coaxial cables and transceiver source impedance have been adopted .
Doug N4HNH video is here: https://youtu.be/dM9Ww37afYs