Te whakamāramatanga o te pūmanawa hiko
Ko te pūmanawa hiko te tikanga o te pūngao pūmanawa hiko mō ia wae utu. Mehemea kei te pūwāhi a, ko te pūngao pūmanawa hiko o te utu q he rite ki te EP a , kātahi ka hangaia te pūmanawa hiko i te pūwāhi a penei:
V = pūmanawa hiko, EP = pūngao pūmanawa hiko, q = utu hiko
Ehara i te mea kei te pūwāhi a anake a V engari kei ngā pūwāhi katoa o te mara hiko. Hei tauira, ka whakamahia te pūwāhi a. Ka whakamāramahia i muri mai, kāore te V e whakawhirinaki ki te utu q.
He rahinga tauine te EP me te utu hiko, nō reira kei roto hoki i te V ngā rahinga tauine. Ko te wae pūnaha ā-ao o te EP ko Joule, ā, ko te wae pūnaha ā-ao o te utu hiko ko Coulomb, nō reira ko te wae pūnaha ā-ao o te V ko Joule ia Coulomb (J/C). Ko tētahi atu ingoa mō J/C ko te Volt, i ahu mai i te ingoa o te kaipūtaiao Itari me te kaihanga o te pākahiko hiko, a Alessandro Volta (1745-1827).
Te rerekētanga pūmanawa hiko
Kāore e taea te mōhio ki te V i tētahi pūwāhi pērā i te V i te pūwāhi a, arā, ko V a , nā te mea ko te mea nui ko te huringa o te pūmanawa hiko. Ka taea te mōhio ki ngā huringa o te pūmanawa hiko mā tōna uara, mā roto i ngā tātaitanga, i ngā inenga rānei. Ka huri te V ina neke te utu q mai i tētahi pūwāhi ki tētahi atu. Mehemea ka neke te utu q mai i te pūwāhi a ki te pūwāhi b, ko te huringa o te V ko:
Ko te Vab he rerekētanga V i waenga i ngā pūwāhi e rua i roto i te papa hiko, hei tauira, ko ngā pūwāhi a me te b. Ko te rerekētanga o te V i waenga i ngā pūwāhi a me te b (V ab ) he rite ki te mahi i mahia e te kaha hiko i roto i te utu hiko i te neke mai i te pūwāhi a ki te pūwāhi b, mō ia utu (W ab / q). Me mōhio ko te mahi i mahia e te kaha hiko o te utu q i te neke mai i te pūwāhi a ki te pūwāhi b (W ab ) he rite ki te huringa o te kaha pūmanawa hiko o te utu q (ΔEP). Nō reira, i roto i te whārite i runga ake nei, ka taea te whakakapi i te ΔEP ki te W ab.
Ina kei te teitei tetahi mea i runga ake i te mata o te whenua, he kaha pūmanawa tōpana tōna, ā, ka whakamahia te mata o te whenua hei pūwāhi tohutoro. I tēnei wā, ka whakatakotoria te teitei o te mata o te whenua me te kaha pūmanawa tōpana i te mata o te whenua ki te kore. He rite ki te kaha pūmanawa tōpana, ina kīia he pūwāhi he pūmanawa hiko motuhake tō tetahi pūwāhi, me waiho hei pūwāhi tohutoro, me te whakaaro noa ki te rerekētanga o te pūmanawa hiko ka taea te tatau. I te nuinga o te wā, ka whiriwhiria ngā kaiārahi whenua, ngā kaiārahi hiko rānei e hono ana ki te whenua hei pūwāhi tohutoro, ā, ka whakatakotoria te pūmanawa hiko o te kaiārahi, te pūmanawa hiko rānei i roto i te whenua ki te kore. Nō reira, ki te mea he 12 Volts te kaha hiko o tētahi pūwāhi, ko te rerekētanga pūmanawa hiko i waenga i taua pūwāhi me te whenua he 12 Volts. I te pākahiko 6 Volt, ko te rerekētanga pūmanawa hiko i waenga i te pito pai me te pito kino he 6 Volts. Nā te mea ko te waeine o te rerekētanga pūmanawa hiko ko Volt, ko te rerekētanga pūmanawa hiko i waenga i ngā pūwāhi e rua ka kiia ko te ngaohiko.
Ka taea te tuhi anō i te whārite rerekētanga pūmanawa hiko i runga ake nei penei:
Ki te haere te utu q mā roto i te rerekētanga pūmanawa hiko V ab , ka rerekē te pūngao pūmanawa mā te ΔEP. Hei tauira, ka haere te utu o te 2 Coulomb mā roto i te rerekētanga pūmanawa hiko o te 12 Volts, ka rerekē te pūngao pūmanawa hiko mā te (2 C)(12 V) = 24 Joules. Waihoki, ki te haere te utu 4 Coulomb mā roto i te rerekētanga pūmanawa hiko o te 24 Volts, ka rerekē te pūngao pūmanawa hiko mā te (4 C) (24 V) = 96 Joules.
Nō reira, ko te huringa o te pūngao pūmanawa hiko (ΔEP) he rite ki te utu (q) me te ngaohiko (V ab ). Ka teitei ake te utu hiko me te ngaohiko, ka teitei ake te huringa o te pūngao pūmanawa hiko. E pā ana te pūngao pūmanawa ki te kaha ki te mahi, nō reira, ki te mea he nui ngā huringa o te pūngao pūmanawa hiko, he nui anō hoki te kaha ki te mahi.
He whārite whānui tonu te whārite o te rerekētanga V i runga ake nei. Hei tiki i tētahi whārite V taipitopito ake, arotakehia te rerekētanga pūmanawa hiko i roto i te papa hiko ōrite me te rerekētanga pūmanawa hiko i hangaia e te utunga kotahi.
Te pūmanawa hiko i roto i te mara hiko ōrite
Ka taea te tatau i te rerekētanga o te V i waenga i ngā pūwāhi e rua i roto i tētahi papa hiko ōrite, hei tauira, te pūwāhi a me te pūwāhi b, mā te whakamahi i te whārite i raro nei:
V ab = te rerekētanga V i waenga i ngā pūwāhi e rua, E = te papa hiko, me d = te tawhiti i waenga i ngā pūwāhi e rua.
V i hangaia e te utunga kotahi
Ka taea te tatau i te V i tētahi pūwāhi nā te utu kotahi e whakaputa ana i te āpure hiko mā te whakamahi i te whārite:
V ab = te rerekētanga V i waenga i ngā pūwāhi e rua, k = te pūmau Coulomb, Q = te utunga kotahi e whakaputa ana i te āpure hiko, r = te tawhiti i waenga i te utunga Q me te pūwāhi e tatauhia ai te V.
Te whanaungatanga i waenga i te mara hiko (E) me te pūmanawa hiko (V)
He rahinga whārite te mara hiko E, ko te V ia he rahinga tauine. Ko te rahinga whārite e pā ana ki te ahunga, nō reira he uaua ake te tatau i te whakataurite ki te tatau i ngā rahinga tauine. Hei whakahaere i te tatau i te mara hiko, whakamahia he whārite e whakaatu ana i te whanaungatanga i waenga i te mara hiko me te V.
Kua tuhia anōtia te whārite rerekētanga pūmanawa i whakaahuatia i mua ake nei penei:
I roto i te pāngarau, ko te mahi te hua o te kaha me te nekehanga, ko te kaha te hua o te utu me te mara hiko. Ko te whanaungatanga i waenga i te mahi, te kaha, me te nekehanga e whakaatuhia ana mā te whārite i raro nei:
Ki te honoa ngā whārite e rua i runga ake nei, ka puta te whārite hou penei:
E = te papa hiko, V ab = te rerekētanga pūmanawa hiko i waenga i ngā pūwāhi e rua pēnei i ngā pūwāhi a me b, d = te tawhiti i waenga i ngā pūwāhi e rua.
Ko te ine o te rerekētanga pūmanawa ko te Volt, ā, ko te ine o te tawhiti ko te mita kia taea ai te kī i te papa hiko i roto i ngā ine o Volts ia mita (V/m).
Ka taea te whakamahi i tēnei whārite hei whakatau i te āpure hiko (ōrite) e mōhiotia ana ko te rerekētanga pūmanawa i waenga i ngā pūwāhi e rua me te tawhiti i waenga i ngā pūwāhi e rua. I runga i te whārite, he ōrite te āpure hiko ki te V, ā, he ōrite whakamuri ki te tawhiti. Ko te tikanga tēnei, ko te teitei ake o te V, ko te teitei ake o te āpure hiko, ā, ko te teitei ake o te tawhiti, ko te iti ake o te āpure hiko.
