Labarin kan wutar lantarki ya tattauna yawan wutar lantarki, kuma an kuma yi bayanin filin lantarki a cikin labarin kan filayen lantarki. Filin lantarki da wutar lantarki suna wanzuwa a cikin mai jagora lokacin da akwai bambancin yuwuwar a tsakanin mai jagora; akasin haka, idan babu wani bambanci mai yuwuwa, babu filin lantarki ko wutar lantarki.
A cikin na'urar sarrafa ƙarfe, filin lantarki yana daidai gwargwado kai tsaye da yawan wutar lantarki, inda rabon filin lantarki zuwa yawan wutar lantarki yake akai-akai. Rabon filin lantarki zuwa yawan wutar lantarki ana kiransa juriya ko takamaiman juriya . A lissafi, dangantakar da ke tsakanin filin lantarki, yawan wutar lantarki, da takamaiman juriya an bayyana ta a cikin lissafi:
Bayani: ρ = takamaiman juriya, E = filin lantarki, J = yawan wutar lantarki
Ɗaya daga cikin dabarun filin lantarki shine E = V/s inda V = bambancin ƙarfin lantarki = ƙarfin lantarki da s = nisa, don haka naúrar filin lantarki shine Volt/mita (V/m). Tsarin yawan yanzu shine J = I/A inda I = wutar lantarki da A = yankin giciye na mai jagoranci, don haka naúrar yawan yanzu shine murabba'in Ampere/mita (A/m2 ) . Tsarin juriya shine ρ = E/J don haka naúrar juriya shine V/m: A/m2 = V/mxm2 / A = V/A (m) = Ω m (karanta: mita Ohm). Ω = Volt/Ampere naúrar juriya ce ta lantarki, game da wannan naúrar an yi bayani a cikin labarin game da dokar Ohm.
Mafi girman ƙimar juriya suna da na'urorin hana lantarki ko masu sarrafa wutar lantarki marasa kyau, yayin da mafi ƙarancin ƙimar juriya suna da na'urorin sarrafa wutar lantarki ko masu sarrafa wutar lantarki masu kyau. Mafi kyawun mai sarrafa wutar lantarki yana gudanar da wutar lantarki, haka nan ƙarancin juriyarsa . Tsarin masu sarrafa ƙarfe waɗanda ke da mafi girman juriya zuwa mafi ƙanƙanta shine tin, ƙarfe, aluminum, zinariya, jan ƙarfe, azurfa. Don haka za a iya kammala da cewa ƙimar juriya na abu yana nuna ma'aunin ikon abu na hana wutar lantarki.
Mai jagoranci mai kyau wanda ke bin dokar Ohm, a wani yanayi mai zafi, ƙimar juriyarsa ba ta dogara da filin lantarki ba, ma'ana idan girman filin lantarki ya canza, ƙimar juriya ba ta canzawa. Akasin haka, mai jagoranci wanda bai bi dokar Ohm ba, ƙimar juriyarsa ta dogara ne akan filin lantarki, ma'ana idan girman filin lantarki ya canza, ƙimar juriyarsa ma ta canza.
Juriyar na'urar sarrafa ƙarfe ta dogara ne da zafin jiki. Yayin da zafin jiki ke ƙaruwa, juriyar tana ƙaruwa; akasin haka, yayin da zafin jiki ke raguwa, juriyar tana raguwa. Yayin da zafin jiki ke ƙaruwa, ƙwayoyin halitta suna motsawa da sauri kuma suna zama marasa tsari, suna hana motsin electrons, suna rage guduwarsu. Yayin da zafin jiki ke raguwa, ƙwayoyin halitta suna motsawa a hankali kuma suna zama masu tsari, wanda ke ba da damar kwararar electrons mai santsi.
Juyin juriya shine juyi. A lissafi, dangantakar da ke tsakanin juriya da juyi ana bayyana ta ta hanyar lissafi:
σ = 1/ρ
Bayani: σ = ƙarfin lantarki, ρ = juriyar direba.
Naúrar juriya ita ce Ωm don haka naúrar watsawa ita ce 1/Ωm = (Ωm)-1
Masu sarrafa wutar lantarki ko masu sarrafa wutar lantarki masu kyau suna da mafi girman ƙimar wutar lantarki yayin da mafi ƙarancin ƙimar wutar lantarki suna da masu hana wutar lantarki ko masu sarrafa wutar lantarki marasa kyau. Mafi kyawun mai sarrafa wutar lantarki yana gudanar da wutar lantarki, haka nan mafi girman ƙarfin wutar lantarki yake. Tsarin masu sarrafa ƙarfe waɗanda ke da mafi girma zuwa mafi ƙanƙantar ƙarfin lantarki shine azurfa, jan ƙarfe, zinariya, aluminum, ƙarfe, tin. Don haka za a iya kammala da cewa ƙimar wutar lantarki na wani abu yana nuna ma'aunin ikon abin na'urar lantarki. Azurfa tana da babban ƙarfin lantarki amma tana da tsada don haka ana amfani da jan ƙarfe sosai a matsayin mai sarrafa wutar lantarki.
