What physical property does K Band primarily measure?

K Band primarily measures radio waves, which are part of the electromagnetic spectrum. This frequency range typically encompasses wavelengths from approximately 1 millimeter to 10 millimeters, corresponding to frequencies between 30 GHz and 300 GHz. K Band is commonly used in various applications, particularly in radar systems, including speed enforcement, weather monitoring, and satellite communications.

Understanding that K Band focuses on radio waves is essential because it highlights the technology's reliance on non-ionizing radiation to detect the presence and distance of objects. This is in stark contrast to the other options; for instance, sound waves are mechanical vibrations that require a medium to propagate, while electrical resistance pertains to the opposition to current flow in a conductor, and thermal energy relates to the heat content within a substance. Hence, radio waves being the correct focus of K Band encapsulates its operational principles and applications in radar technology effectively.