Thaum ib alternating tam sim no dhau los ntawm ib tug hlau, ib tug alternating magnetic teb yog generated nyob ib ncig ntawm lub hlau. Sab hauv ntawm tag nrho cov neeg xyuas pib nyob rau hauv alternating magnetic teb yuav tsim ib tug induced tam sim no. Txij li qhov kev cuam tshuam tam sim no tsim lub voj kaw hauv tag nrho tus neeg xyuas pib, zoo li lub vortex dej, nws yog hu ua eddy tam sim no. Eddy tam sim no yuav tsis tsuas yog khib nyiab hluav taws xob hauv vain, txo qhov ua tau zoo ntawm kev siv cov khoom siv hluav taws xob, tab sis kuj ua rau cov khoom siv hluav taws xob cua sov (xws li transformer hlau core), uas yuav cuam tshuam rau kev ua haujlwm ntawm cov khoom siv hauv cov xwm txheej hnyav.