Khoom Siv Kho Khoom Siv thiab Kev Xa Khoom

Electromagetic thiab Fais Fab Kab Rwb thaiv tsev zaj duab xis tiv xwm txheej, ib leeg-txheej winding thiab ntau-txheej winding thiab ntau-txheej txheem nrawm thiab winding yog kho tau