Wasu mutane suna tambayar cewa kebul ɗin dumama mai iyakance kai shine kebul na dumama, ƙarfin wutar lantarki na ɓangaren farko da na ƙarshe yakamata ya zama daidai, kuma zafin dumama kowane sashe ya zama daidai. Ta yaya za a iya samun ƙananan zafin jiki a ƙarshe? Ya kamata a yi nazarin wannan daga ka'idar bambancin wutar lantarki da ka'idar zafin jiki mai iyakancewa.

Menene bambancin wutar lantarki? Lokacin da halin yanzu ya wuce ta hanyar kebul na dumama wutar lantarki, za a sami bambancin ƙarfin lantarki tsakanin iyakarsa biyu. Ayyukan wutar lantarki shine don taimakawa halin yanzu ya wuce ta juriya a hankali kuma ya samar da madauki. Mafi girman juriya, mafi girman canjin canjin wutar lantarki.

Kebul ɗin dumama zafin jiki mai iyakance kansa yana da halayen canzawa tare da canjin yanayin yanayi. Babban zafin jiki na yanayi zai ƙara juriya kuma ya rage wucewar halin yanzu. Yanayin zafi a ƙarshen wutsiya yana da ƙasa, wanda zai iya zama saboda juriya ya zama mafi girma, ƙarfin wucewa ya zama ƙarami, kuma bambancin wutar lantarki tsakanin kai da iyakar wutsiya ya zama babba, wanda kuma al'ada ne.

Wani dalili kuma shine cewa tsawon kebul ɗin dumama zafin jiki mai iyakance kansa ya wuce yayin aikin shigarwa. Saboda ƙarancin zafin jiki na zafin jiki na wutar lantarki mai juriya zai canza tare da zafin jiki, mafi girman juriya a ƙarshen kebul na dumama, ƙananan zafin jiki. Don kauce wa wannan yanayin, dole ne a adana wani tsayin igiyoyin dumama wutar lantarki yayin shigarwa.