ampere

views updated May 17 2018

ampere (symbol A) SI unit of electric current. It is defined as the current in a pair of straight, parallel conductors of infinite length and 1m (39in) apart in a vacuum that produces a force of 2 × 10−7 newton per metre in their length. This force may be measured on a current balance instrument, the standard against which current meters, such as an ammeter, are calibrated.

ampère

views updated Jun 08 2018

ampère unit of electric current. XIX. f. name of A. M. Ampère (d. 1836); adopted by the Congrès Électrique at Paris, 1881. abbrev. amp.

ampere

views updated May 29 2018

ampere (am-pair) n. the basic SI unit of electric current. It is equal to the current flowing through a conductor of resistance 1 ohm when a potential difference of 1 volt is applied between its ends. Symbol: A.