12 volt dc lub cev muaj zog qhia koj lub mis rau xam cov khoom tsim tawm ntawm DC lub cev muaj zog thiab lub zog nkag.
DC lub cev muaj zog tawm thiab cov tswv yim fais fab kev xam lub zog, lub zog hluav taws xob xam cov lej, ntau qhov hluav taws xob los ntawm qhov tam sim no, cov qauv no yog cov lus txhais ntawm lub zog hluav taws xob, ib txwm raug, tsim nyog rau txhua yam xwm txheej.
Rau cov khoom siv hluav taws xob tsis zoo, xws li cov xov hluav taws xob tiv thaiv, qhov muag teev, thiab lwm yam, koj tuaj yeem siv tus qauv ntawm "square ntawm qhov tam sim no sib npaug los ntawm kev ua haujlwm" thiab "square ntawm qhov hluav taws xob tau faib los ntawm kev ua haujlwm", uas yog los ntawm Ohm txoj cai.
Txawm li cas los xij, rau cov tsis muaj ntshiab resistor circuits, xws li lub cev muaj zog, tsuas yog cov qauv ntawm "voltage khoo tam sim no" yuav siv tau, vim tias Ohm txoj cai tsis siv rau cov motors, thiab lwm yam, uas yog, voltage thiab tam sim no tsis sib npaug. Qhov no yog vim tias lub cev muaj zog "tsim kom muaj lub zog rov qab" thaum lub zog khiav. Piv txwv li, qhov hluav taws xob sab nraud yog 8 volts, qhov tsis kam yog 2 ohms, thiab lub zog rov qab electromotive yog 6 volts. Qhov tam sim no ntawm lub sijhawm no yog (8-6) / 2 = 1 (ampere) hloov 4 amps. Yog li ntawd lub hwj chim yog 8 x 1 = 8 (watts).
Ib qho ntxiv, Joule txoj cai yog cov qauv rau lub cua sov ua haujlwm. Lub zog cua kub yog "tam sim no txiav los ntawm kev tsis kam", uas ib txwm yog.
Kuj tseem ua piv txwv saum toj no, lub zog ntawm lub cev muaj zog cua sov yog 1 × 1 × 2 = 2 (ວັດ), uas yog, lub zog ntawm lub cev muaj zog tag nrho yog 8 watts, lub zog cua kub yog 2 watts, thiab seem 6 watts yog siv rau Kev Tshawb Fawb.
P = IU, feem ntau paub ua cov qauv mis, uas yog, thaum nws tuaj yeem siv tau;
P = Kuv ^ 2 * R, siv thaum qhov tam sim no hauv Circuit Court sib npaug lossis thaum xam qhov hluav taws xob cua sov;
P = U ^ 2 / R, siv thaum cov voltages hauv Circuit Court yog sib npaug.
