Lub commutator yog ib feem tseem ceeb ntawm dc lub cev muaj zog thiab AC commutator armature.
Feem ntau cov teeb meem yog tsim los ntawm cov molecules uas yog tsim los ntawm atoms uas nyob rau hauv lem yog ua los ntawm nuclei thiab electrons. Hauv ib qho atom
