Ampere-Turn
/ˈæm.pɪər tɜːrn/noun
A unit of magnetomotive force equal to the magnetic effect produced by one ampere of current flowing through one turn of a coil.
Did you know?The word combines a unit named after physicist André-Marie Ampère with “turn,” because each loop of wire adds to a coil’s magnetizing force.
Etymological Timeline
Proto-Indo-European
PIE
*ter-
“A reconstructed root associated with rubbing, boring, or turning.”
Ancient Greek
Greek
tórnos
“A compass or turning tool used to draw circles.”
Classical Latin
Latin
tornāre
“To turn on a lathe or shape by rotation.”
Middle English
English
turnen
“To rotate, change direction, or transform.”
1820s
French
ampère
“The surname-derived name honoring André-Marie Ampère, whose work established foundational laws of electromagnetism.”
1881
International scientific usage
ampere
“The electrical unit adopted in honor of Ampère.”
Late 19th Century
English
ampere-turn
“A measure of magnetomotive force based on current multiplied by the number of coil turns.”
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