Tsab xov xwm hais txog Qhov chaw ntawm electromotive force emf Internal resistance Terminal voltage
Hluav taws xob tam sim no ntws hauv lub voj voog kaw, los ntawm lub zog siab mus rau lub zog qis. Thaum lub zog hluav taws xob txav mus los ntawm ib feem ntawm kev tiv thaiv hluav taws xob, muaj kev txo qis hauv lub zog hluav taws xob vim tias lub zog hluav taws xob siv rau qhov kev tiv thaiv no. Yuav kom cov hluav taws xob txuas ntxiv mus los ntawm lub zog siab mus rau lub zog qis,
Yuav tsum muaj ib lub cuab yeej los ntxiv lub zog hluav taws xob, lub cuab yeej yog lub zog electromotive (emf) lossis qhov tseeb dua hu ua qhov chaw hluav taws xob. Emf lossis qhov chaw hluav taws xob yog ib qho khoom siv uas hloov ib hom zog mus rau hauv lub zog hluav taws xob, xws li roj teeb, lub hnub ci hlwb, lossis cov tshuab hluav taws xob.
Qhov chaw ntawm lub zog hluav taws xob (emf)
Daim duab nyob ib sab yog ib daim duab yooj yim ntawm lub voj voog kaw uas muaj emf (ε) thiab tsis kam (R). Cov kab ntsug ntev ntawm qhov chaw emf sawv cev rau lub zog siab, thaum cov kab ntsug luv sawv cev rau lub zog qis. Cov nqi hluav taws xob txav mus los ntawm lub zog siab mus rau lub zog qis. Lub zog hluav taws xob uas txav mus rau lub sijhawm tshwj xeeb hu ua hluav taws xob tam sim no, qhov twg qhov kev taw qhia ntawm cov hluav taws xob tam sim no yog qhia los ntawm tus xub.
Thaum nws nyob ntawm qhov muaj peev xwm siab, lub zog hluav taws xob muaj zog. Lub zog hluav taws xob txo qis thaum lub zog hluav taws xob txav mus dhau lub resistor. Thaum lub zog hluav taws xob txav mus rau hauv qhov chaw ntawm emf los ntawm qhov muaj peev xwm qis mus rau qhov muaj peev xwm siab, lub zog hluav taws xob nce ntxiv.
Sab hauv tsis kam
Thaum lub zog hluav taws xob txav mus rau hauv qhov chaw ntawm emf, cov nqi raug kev tiv thaiv. Qhov chaw hluav taws xob tiag tiag hauv lub neej feem ntau muaj kev tiv thaiv sab hauv, uas yog qhia los ntawm lub cim r. Thaum lub zog hluav taws xob ntws los ntawm qhov tsis kam sab hauv (r), muaj lub zog hluav taws xob txo qis.
Qhov hluav taws xob kawg
Qhov hluav taws xob kawg (V) yog qhov hluav taws xob tag nrho uas tsim los ntawm qhov chaw hluav taws xob lossis qhov chaw ntawm emf. Hauv lej, qhia los ntawm cov qauv:
V = ε – Kuv r
V = Qhov hluav taws xob kawg, ε = emf, I = tam sim no hluav taws xob, r = kev tiv thaiv sab hauv.
Yog tias lub roj teeb 12 Volt muaj qhov tsis kam ntawm 0.2 Ω ces thaum 2 A ntws los ntawm lub roj teeb, qhov hluav taws xob kawg yog 12 – (0.2) (2) = 12 – 0.4 = 11.6 Volt.
Thaum tsis muaj hluav taws xob ntws los ntawm lub roj teeb, qhov hluav taws xob kawg = emf. Xav tias emf = 12 Volts, ces qhov hluav taws xob kawg = 12 Volts. Yog tias muaj hluav taws xob ntws los ntawm qhov chaw ntawm emf, qhov hluav taws xob kawg me dua li emf.
Emf yog qhov hluav taws xob uas teev nyob rau ntawm lub roj teeb, piv txwv li, thaum qhov hluav taws xob kawg yog qhov hluav taws xob tiag tiag lossis qhov sib txawv ntawm lub zog tiag tiag, qhov twg tus nqi raug cuam tshuam los ntawm cov hluav taws xob ntws hauv lub roj teeb.
