Assertion: atomic clock | /r/HasProperty | a clock device
Facets:
Source sentences:
text: An atomic clock is a clock device (time standard) that uses a hyperfine transition frequency in the microwave, or electron transition frequency in the optical or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element.
text: An atomic clock is a clock device that uses an electronic transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element.