wheatstone bridge

Wheat·stone bridge   (hwēt'stōn', wēt'-)    (click for larger image in new window) n.  An instrument or a circuit consisting of four resistors or their equivalent in series, used to determine the value of an unknown resistance when the other three resistances are known. [After Sir Charles Wheatstone (1802-1875), British physicist and inventor.]

Main Entry: Wheat·stone bridge
Pronunciation: "hwEt-"stOn-, "wEt-, chiefly Brit -st&n-
Function: noun
: a bridge for measuring electricalresistances that consists of a conductor joining two branches of a circuit
Wheatstone, Sir Charles (1802–1875), British physicist. Wheatstone was professor ofexperimental philosophy at King's College, London. He is remembered for his researches in electricity, sound, and light. In 1834 he devised a revolving mirror for an experiment to measure the speed ofelectricity in a conductor. In 1843 he constructed the Wheatstone bridge and began to popularize its use. He initiated the use of electromagnets in electric generators, and in 1837 he and Sir WilliamFothergill Cooke patented an early telegraph.