Coaxial cable is two conductors sharing the same axis (hence 'coaxial'):
The shield carries the return current. If one or both ends has a transformer it need not be at ground.
Traditional telegraph wires used only a single wire, and the return current was carried through the ground.
These are both electric transmission methods- they work down to DC. There is only one way to transmit with no path for return current: using electromagnetic radiation.
Coaxial cable is two conductors sharing the same axis (hence 'coaxial'):
Coaxial cable is two conductors sharing the same axis (hence 'coaxial'):
The shield carries the return current. If one or both ends has a transformer it need not be at ground.
Traditional telegraph wires used only a single wire, and the return current was carried through the ground.
These are both electric transmission methods- they work down to DC. There is only one way to transmit with no path for return current: using electromagnetic radiation.
