1. Lub zog siv hluav taws xob (P, chav tsev: watts, W) yog lub zog hluav taws xob tiag tiag siv rau ntawm lub nra, siv rau kev ua haujlwm muaj txiaj ntsig thiab koom ncaj qha rau kev hloov hluav taws xob. Piv txwv li, lub tshuab hluav taws xob hloov hluav taws xob hloov hluav taws xob mus rau hauv lub tshuab hluav taws xob, thiab lub teeb lub teeb hloov hluav taws xob rau hauv lub teeb lub zog, muab lub zog xav tau rau cov khoom siv hluav taws xob xws li motors, heaters, lighting equipment, etc.
2. Reactive zog (Q, unit: reactive, VAR) yog hais txog lub sij hawm lub zog pauv ntawm reactive yam (xws li inductors thiab capacitors) thiab lub hwj chim qhov chaw nyob rau hauv ib tug AC Circuit Court. Nws tsis ua haujlwm zoo, tab sis txhawb nqa lub zog cia rau cov hlau nplaum lossis hluav taws xob. Reactive zog yog siv los tsim thiab tswj cov hlau nplaum lossis hluav taws xob, tsis yog ua haujlwm ncaj qha. Nws txhawb kev ua haujlwm ib txwm muaj ntawm cov khoom siv xws li transformers thiab motors, kom ntseeg tau tias cov khoom siv no tuaj yeem tsim thiab xa cov hluav taws xob electromagnetic.