Isibalo sokumelana kukagesi
Esihlokweni somthetho ka-Ohm, kutholakale ifomula echaza ubudlelwano phakathi kwe -voltage (V), i-electric current (I), kanye nokumelana kagesi (R). Ivezwe ngokwezibalo ngezibalo:
Lesi sibalo sibonisa ukuthi ukumelana kukagesi (R) kuhambelana ngqo ne-voltage kagesi (V) futhi kuhambisana ngokuphambene nomsinga kagesi (I). Uma i-voltage enkulu inkulu kunokumelana kukagesi kuya kuba kukhulu, ngokuphambene nalokho, uma amandla kagesi eba makhulu kunokumelana kukagesi kuzoba kukhulu. Lesi sibalo sichaza umthetho we-Ohm kuphela uma ukumelana kukagesi (R) kungaguquki. Uma ukumelana kukagesi kungaguquki, khona-ke lesi sibalo asichazi umthetho we-Ohm, kodwa sichaza ukumelana komqhubi.
Esihlokweni mayelana nomthetho ka-Ohm, ubudlelwano phakathi kokumelana komqhubi kagesi (R), ukumelana kohlobo noma ukumelana komqhubi (ρ), ubude bomqhubi (l), kanye nendawo yesigaba somqhubi (A) buchazwe ngokwezibalo kulesi sibalo:
Ngokusekelwe kulesi sibalo, kuphethwa ngokuthi ukumelana kukagesi kuhambelana ngqo nokumelana kohlobo nobude bomqhubi, kodwa kuhambelana ngokuphambene nendawo enqamulayo yomqhubi. Ngamanye amazwi, ukumelana kukagesi kuyanda lapho ukumelana kohlobo nobude bomqhubi kuyanda, kanti ukumelana kukagesi kuncipha uma indawo enqamulayo yomqhubi ikhula.
Uma ubude bomqhubi (l) kanye nendawo enqamulayo (A) kungaguquguquki, ukumelana kukagesi (R) kuncike kuphela ohlotsheni lokumelana (ρ). Uma uhlobo lokumelana lukhula, ukumelana kukagesi kuyanda, ngokuphambene nalokho uma uhlobo lokumelana luncishisiwe khona-ke ukumelana kukagesi kuyancipha. Inani lokumelana lohlobo ngalunye lomqhubi lilingana ngqo nokushisa,
uma izinga lokushisa liphakama kunohlobo lokumelana olukhula kakhulu noma okuphambene nalokho, uma izinga lokushisa liphansi kunokumelana kohlobo olukhula kancane.
Uhlobo oluphambene lokumelana (ukumelana) ukuqhutshwa komoya. Ukuqhutshwa komoya kuhambisana ngokuphambene nokungavumi, njengoba kushiwo ku-equation engezansi:
Uma kuvezwa ekuqhubeni amandla, i-equation 2 ishintshela ku:
Ngokusekelwe kulesi sibalo, kungaphethwa ngokuthi ukumelana kukagesi kuhambisana ngokuphambene nokuqhuba,
uma ukuqhutshwa komqhubi kukhulu kunokumelana kukagesi kuba kuncane noma okuphambene nalokho, uma ukuqhutshwa komqhubi kuba kuncane kunokumelana kukagesi kukhulu.
Inani lokumelana lohlobo ngalunye lwezinto ezibonakalayo liboniswe kuthebula elingezansi.
Iyunithi yokumelana
Iyunithi kagesi yiVolt, iyunithi yamandla kagesi yi-Ampere ngakho iyunithi yokumelana kagesi yiVolt / Ampere. I-Volt / Ampere ibizwa nangokuthi i-Ohm efanekiselwa yi-Ω, iqonda uGeorg Simon Ohm (1789-1854), isazi sefiziksi saseJalimane. Ngaphandle kwe-Ohm, isetshenziswa futhi amayunithi e-kilo-ohm kanye ne-megaohm. 1 kilo-ohm (kΩ) = 1000 Ω = 10 3 Ω, kuyilapho i-1 mega-ohm (MΩ) = 1000,000 Ω = 10 6 Ω.
Amathuluzi okulinganisa ukumelana
Ithuluzi lokulinganisa ukumelana nogesi yi-ohmmeter. Leli thuluzi lokulinganisa lihlanganiswe ne-multimeter, idivayisi yokulinganisa i-voltage kagesi, i-electron current, kanye nokumelana nogesi.
