Which term describes the hollow metal conductor that guides microwaves and is filled with inert gas?

• A. SERRATED RANGE RINGS
• B. Power Line Effect
• C. Water in the Waveguide
• D. Sub Refraction

Answer: (C)

A hollow metal tube that guides microwaves is called a waveguide. To handle very high power, the inside of a waveguide is often kept dry by filling it with an inert gas, which raises the breakdown voltage and reduces the chance of arcing or ionization of the air. The usual term for this setup is a gas-filled waveguide. Moisture inside a waveguide would be undesirable because it changes the dielectric properties and causes losses or arcing, so keeping the interior dry with inert gas is key. If this choice is presented as the term in some materials, it’s highlighting the interior condition inside the guide rather than naming the device itself; the standard name for the device is a gas-filled waveguide.