Metrication in the United States There are no U.S. customary units for electric current, potential difference, or charge since these concepts were developed after the international adoption of metric in science. The metric units ampere, volt, ohm and coulomb are the only units used. The SI term hertz has replaced the term "cycles per second" as a unit of frequency. Energy is often measured in watt hours, BTUs, therms or calories rather than the SI joule. Residential and commercial electrical energy use is metered and billed in kilowatt hours, kW·h, as in most metric countries. Force measurements regularly use the pound instead of the SI
USS Ampere equipment was transferred to "USS Surfbird", a minesweeping vessel which was redesignated a degaussing ship on 15 June 1957. She remained in reserve in the Far East until the summer of 1961, when the decision was made to dispose of her. Her name was struck from the Naval Register on 1 July 1961, and she was sold on 21 June 1962, to the Philippine President Lines of Manila. Her final disposition is unknown. USS Ampere USS "Ampere" (PCE-919/AM-359/YDG-11/ADG-11) was originally planned as a for the United States Navy, "PCE-919", and laid down as an , named "Drake", for the male