永えい久きゅう磁じ場ば

noun

permanent magnetic field

Technical term in physics and engineering for a magnetic field that does not change over time, typically produced by a permanent magnet.

• 永えい久きゅう磁じ場ばを利り用ようしたモーターは、効こう率りつが高たかい。

  Motors that use a permanent magnetic field are highly efficient.