Papa Aukume huri noa i te Auhiko Hiko
Pengantar
He āhuatanga taiao te papa aukume e puta ana i te taha o te au hiko. Ina rere te au hiko i roto i te kaiārahi, ka hangaia he papa aukume e karapoti ana. I kitea tuatahitia tēnei āhuatanga e Hans Christian Ørsted i te tau 1820. I kitea e Ørsted ka piko te ngira kāpehu ina whakatakotoria ki te taha o te waea e kawe ana i te au, e tohu ana i te aroaro o te papa aukume e karapoti ana i te waea. Nā tēnei kitenga i whakatakoto te ara mō te whanaketanga o te aukume hiko, te pūtake o te nuinga o ngā hangarau hou.
Ariā Taketake
Ka taea te whakamārama i te papa aukume e puta mai ana i te au hiko mā te ture Biot-Savart me te ture a Ampère. E kī ana te ture Biot-Savart ka puta mai he papa aukume i tētahi huānga iti o te au hiko. Mā te pāngarau, ka whakaaturia tēnei ture penei:
\[ \mathbf{dB} = \frac{\mu_0}{4\pi} \frac{I \mathbf{dl} \times \mathbf{\hat{r}}}{r^2} \]
Kei hea:
– Ko te \(\mathbf{dB}\) te papa aukume i hangaia e te huānga iahiko \(\mathbf{dl}\),
– Ko te uruhanga korehau te \(\mu_0\),
– Ko te iahiko hiko te \(I\),
– Ko \(\mathbf{\hat{r}}\) he ira wae e tohu ana mai i te huānga o nāianei ki te pūwāhi tirotiro,
– Ko te \(r\) te tawhiti i waenganui i te huānga o nāianei me te pūwāhi tirotiro.
Ko te ture a Ampère, i tētahi atu taha, e kī ana ko te papa aukume e huri haere ana i te porowhita kati he rite ki te iahiko e rere ana i roto i taua porowhita. Mā te pāngarau, ka whakaatuhia tēnei ture penei:
\[ \oint \mathbf{B} \cdot d\mathbf{l} = \mu_0 I_{\text{encl}} \]
Kei hea:
– Ko te papa aukume te \(\mathbf{B}\),
– Ko te \(d\mathbf{l}\) he huānga ara,
– Ko \(I_{\text{encl}}\) te iahiko e karapotia ana e te ara kua kati.
Papa Aukume e Hurihuri Ana i te Waea Tika
Mō tētahi waea tika e mau ana i te iahiko hiko, ka taea te tatau i te papa aukume e puta mai ana mā te whakamahi i te ture Biot-Savart. I te tawhiti \(r\) mai i te waea, ko te rahi o te papa aukume \(B\) ko:
\[ B = \frac{\mu_0 I}{2\pi r} \]
He porowhita te āhua o tēnei papa aukume e karapoti ana i te waea, ā, ko te ahunga i whakaritea e te ture ringa matau: ki te tohu te koromatua o te ringa matau ki te ahunga o te iahiko, ko ngā maihao e porowhita ana e tohu ana i te ahunga o te papa aukume.
Papa Aukume huri noa i te Solenoid
He porowhita waea roa te solenoid, he maha ngā hurihanga. Ina rere te iahiko hiko i roto i te solenoid, ka hangaia he papa aukume kaha, ōrite i roto i te solenoid. He ngoikore rawa te papa aukume i waho o te solenoid, ā, ka taea te kī he iti noa iho. Ka taea te tatau i te rahi o te papa aukume i roto i te solenoid pai mā te whakamahi i:
\[ B = \mu_0 n I \]
Kei hea:
– Ko te \(n\) te maha o ngā takahuri mō ia roanga o te solenoid,
– Ko te iahiko e rere ana i roto i te solenoid ko te \(I\).
Te Whakamahinga o te Papa Aukume mai i te Iahiko Hiko
1. Ngā Mōta Hiko me ngā Pūkaha Hiko
Ko te kaupapa o te mahi a ngā motuka hiko ko te iahiko e rere ana i roto i te papa aukume ka puta he kaha. I tetahi atu taha, ka mahi ngā miihini hiko mā te whakaputa i te iahiko ina neke te kaiārahi i roto i te papa aukume. Ka whakamahia e ngā taputapu e rua te papa aukume i hangaia e te iahiko hei huri i te kaha hiko hei kaha miihini, i te ritenga kē rānei.
2. Kaiwhakawhitiwhiti
Ka whakamahia ngā whakawhiti hiko hei whakanui, hei whakaiti rānei i te ngaohiko i roto i tētahi pūnaha tohatoha hiko. Ka mahi ngā whakawhiti hiko i runga i te kaupapa o te whakapūngao hikohiko, arā, ko te hurihanga o te papa aukume i hangaia e te iahiko hiko i roto i te koiri tuatahi ka puta he iahiko hiko i roto i te koiri tuarua.
3. Te Whakaoho Hikohiko
I kitea te āhuatanga o te whakapūngao hikohiko e Michael Faraday, nāna i kī ka taea e te hurihanga o te papa aukume te whakaputa i te iahiko hiko i roto i te kaiārahi hiko. Ka whakamahia tēnei mātāpono i roto i ngā momo tono pēnei i ngā taputapu kite whakarewa, ngā hopuoro, me ngā momo pūoko.
Rangahau me te Whakawhanaketanga Matatau
Kei te whanake tonu te rangahau mō ngā papa aukume me ngā iahiko hiko me ngā whanaketanga hangarau. Ko ētahi o ngā kaupapa rangahau whakamere ko:
1. Ngā Kaiārahi Nui
Ko ngā superconductors he rauemi ka taea te kawe hiko me te kore ātete i ngā pāmahana tino iti. Ko te papa aukume e karapoti ana i te superconductor he āhuatanga ahurei, pērā i te pānga Meissner, e tangohia ai te papa aukume mai i te rauemi superconductor. Ko te whāinga o te rangahau i tēnei mara he whakawhanake i ngā superconductors pāmahana-tiketike ka taea te mahi i ngā pāmahana whaihua ake.
2. Ngā Wai Whakapūngao me te Wai Hiko
Ko ngā wai Magnetorheological (MR) me te electrorheological (ER) he wai ka taea te whakarerekē i te matotoru mā te whakamahi i te papa aukume, te papa hiko rānei. Ka whakamahia ēnei wai i roto i ngā momo mahi pēnei i te whakaiti i te wiri me ngā hononga atamai. Kei te haere tonu te rangahau hei whakapai ake i te mahi me te pumau o ēnei wai.
3. Ngā Rauemi Ferromagnetic me te Nanotechnology
He kaha te aukumetanga o ngā rauemi ferromagnetic, ā, e whakamahia ana i roto i ngā momo taputapu pēnei i te mahara aukume me ngā pūoko. Nā te whanaketanga o te nanotechnology, ka taea te hanga rauemi ferromagnetic i te tauine nanometer hei whakapai ake i tā rātou mahi me te whai huatanga i roto i ngā taputapu hiko.
Whakamutunga
Ko te papa aukume e karapoti ana i te au hiko he āhuatanga taketake i roto i te ahupūngao, he maha ngā whakamahinga whai hua i roto i te oranga o ia rā me te hangarau hou. Mā te mārama ki ēnei papa aukume ka taea e tātou te whakawhanake i ngā taputapu pēnei i ngā motuka hiko, ngā whakaputa hiko, me ngā whakawhiti hiko, he mea nui ki ngā pūnaha tohatoha hiko me ngā hikohiko. Kei te haere tonu te rangahau i tēnei wāhanga, e whakatuwhera ana i ngā whai wāhitanga hou i roto i te hangarau superconducting, ngā wai atamai, me ngā rauemi ferromagnetic. Mā te mārama hohonu ake ki ngā papa aukume me ngā au hiko, ka taea e tātou te whakawhanake tonu i ngā hangarau whai hua me te auaha mō te heke mai.
