Te whakamāramatanga o te ture a Ohm
I roto i te nuinga o ngā ara iahiko whakarewa, he rite te āpure hiko ki te mātotoru o te iahiko hiko, ina he pumau te ōwehenga o te āpure hiko ki te mātotoru o te iahiko hiko. Ka whakaaturia mā te pāngarau mā te whārite:
ρ = E / J
E = papa hiko , ρ = ātete , J = kiato iahiko
Ka kiia te pūmau ρ he ātete, he pūmau tōna uara, ā, kāore e whakawhirinaki ki te papa hiko e puta ai te iahiko.
Ki te piki ake te papa hiko, ka piki ake anō hoki te kiato o te iahiko, engari ki te heke te papa hiko, ka whakaitihia anō hoki te kiato o te iahiko,
kia pumau ai te ōwehenga o te papa hiko ki te mātotoru o te iahiko hiko. Koinei te tauākī ture a Ohm. Nō reira, ko te whārite i runga ake nei e whakamārama ana i te ture a Ohm ina pumau noa a ρ, ā, kāore e whakawhirinaki ki te papa hiko. Kāore te ture a Ohm e pā ana mēnā ka huri te uara o ρ ina huri te papa hiko.
Heoi, he māmā ake te ine i te pūmanawa hiko (V) i te mara hiko (E), nō reira he māmā ake hoki te ine i te iahiko (I) i te kiato o te iahiko (J). Nō reira, haunga te kīanga i roto i te mara hiko, te kiato o te iahiko me te ātete (ρ), ka whakaaturia hoki te ture a Ohm i roto i te pūmanawa hiko, te iahiko me te ātete hiko (R).
Tuatahi, tirohia he ara iahiko waea he roa (l), he horahanga whakawhiti-wāhanga (A) ā, he rerekētanga pūmanawa hiko (V) kei waenganui i ngā pito e rua o te waea. Mena he ōrite te mara hiko ōrite katoa, ko te whanaungatanga i waenganui i te mara hiko me te rerekētanga pūmanawa hiko ka whakaaturia i roto i te whārite V = E s (kua kōrerohia tēnei whārite i roto i te pūmanawa hiko). Mena he ōrite te kiato o ngā iahiko hiko ōrite,
kātahi ka whakaaturia te whanaungatanga i waenga i te iahiko hiko me te mātotoru o te iahiko hiko i roto i te whārite I = JA (kua kōrerohia tēnei whārite i roto i te kaupapa o te iahiko hiko).
Hei whiwhi i tētahi whārite e whakaatu ana i te whanaungatanga i waenga i te pūmanawa hiko (V), te iahiko hiko (I) me te ātete hiko (R),
whakakapia a E me J i roto i te whārite o te ātete, ki a E i roto i te whārite o te pūmanawa hiko me J i roto i te whārite o te iahiko hiko:
He whārite tēnei e whakamārama ana i te whanaungatanga i waenga i te pūmanawa hiko (V), te iahiko hiko (I) me te ātete hiko (R) i roto i te kaiārahi. I runga i tēnei whārite, ka taea te kī ko te ātete hiko i roto i te kaiārahi he whakataurite i te rerekētanga pūmanawa hiko ki te iahiko i roto i te kaiārahi.
E ai ki te ture a Ohm, he pumau te ōwehenga i waenga i te rerekētanga pūmanawa hiko ki te iahiko hiko. Arā, ka whakamāramahia e tēnei whārite te ture a Ohm ina pumau te ātete hiko (R). Kāore e pā te ture a Ohm mēnā kāore te ātete hiko i te pumau.
I roto i te whārite i runga ake nei, he hononga anō tō te ātete hiko (R) i roto i te ara iahiko ki te ātete (ρ), te roa o te ara iahiko (l) me te horahanga whakawhiti-wāhanga (A) o te ara iahiko. E whakaatuhia ana i roto i te whārite mā te pāngarau:
Te whārite o te ture a Ohm
E rua ngā whārite e whakamārama ana i te ture a Ohm, arā, ko ρ = E/J me R = V/I. Me maumahara ko ēnei whārite e rua he whārite o te ture a Ohm ina he pumau a ρ, ā, he pumau a R. Mena ka huri a ρ me R o tētahi kaiārahi, kāore ēnei whārite e whakamārama i te ture a Ohm, engari ko ρ = E/J e whakamārama ana i te ātete o tētahi momo kaiārahi, ā, ko R = V/I e whakamārama ana i te ātete hiko o tētahi kaiārahi.
Ka taea te tuhi i te whārite ρ = E/J pēnei i te E = ρ J. Ina pumau a ρ, ka ōrite a E ki a J, arā, ki te piki a E ka piki a J, ki te heke rānei a E ka heke a J.
Waihoki, ka taea te tuhi i te whārite R = V/I hei V = I R. Ina pumau a R, ka rite tonu te ōrite o V ki a I, arā, ki te piki a V, ka piki a I, ki te heke rānei a V, ka heke a I.
Ko te rauemi e ngohengohe ana ki te ture a Ohm ka kiia he ohmic, ko te rauemi ia kāore e ngohengohe ki te ture a Ohm ka kiia he kore-ohmic. He ohmic te nuinga o ngā kaiārahi whakarewa, ko te nuinga o ngā mea kē atu he kore-ohmic.
Mō ngā mea kore-ohmic, kāore te ātete hiko e pumau, ā, e whakawhirinaki ana ki te iahiko me te rerekētanga pūmanawa hiko. Ko te tikanga, ki te rerekē te iahiko hiko, ka rerekē anō hoki te ātete hiko o te rauemi, ā, ki te rerekē te ngaohiko hiko, ka rerekē anō hoki te ātete hiko o te rauemi. Nā te rerekētanga o te ātete hiko i roto i te mea kore-ohmic, kāore te ngaohiko hiko (V) i te ōrite tika ki te iahiko hiko (I).
Kauwhata V, I me R
I roto i te matū ohmic, he pumau te ōwehenga V ki te I, e tohuhia ana e te rārangi tika. Ko tētahi tauira o te rauemi ohmic ko te kaiārahi konganuku. I roto i te matū kore-ohmic, kāore te ōwehenga o V ki te I i te pumau, e tohuhia ana e te rārangi piko. Ko ngā tauira o ngā rauemi kore-ohmic ko ngā diode semiconductor me ngā transistors.
Ko te ture a Ohm e pā ana ki ngā rauemi ohm anake, kāore e pā ki ngā mea katoa, nō reira kāore e tika kia kīia he ture pēnei i te ture a Newton, i ētahi atu ture ā-tinana rānei. Ko te ture ā-tinana e pā ana ki ngā mea katoa, ehara i te mea ki ētahi mea anake. Engari kua waiho te whakahua i te ture a Ohm hei tikanga, nō reira e kiia tonutia ana ko te ture a Ohm, mena ka maumaharahia ko te ture a Ohm e pā ana ki ngā mea ohm anake.
