Dokar Faraday
Pengantar
Dokar Faraday ta hanyar amfani da na'urar lantarki (electromagnetic induction) wata ƙa'ida ce ta asali a fannin kimiyyar lissafi wadda ke bayyana yadda canjin filin maganadisu zai iya samar da wutar lantarki a cikin na'urar jagora. Michael Faraday ya gano wannan doka a shekarar 1831, kuma muhimmin ginshiƙi ne na na'urar lantarki (electromagnetic) kuma tana da aikace-aikace da yawa a fasahar zamani, kamar janareto da na'urorin canza wutar lantarki. Wannan labarin zai yi cikakken bayani game da ka'idar da ke bayan dokar Faraday, gwaje-gwajen da ke goyon bayanta, da kuma aikace-aikacenta daban-daban.
Ka'idar Asali
Ma'anar Dokar Faraday
Dokar Faraday ta bayyana cewa ƙarfin lantarki (EMF) da aka haifar a cikin da'irar rufewa yayi daidai da saurin canjin kwararar maganadisu ta cikin da'irar. A lissafi, an bayyana wannan doka kamar haka:
\[ \mathcal {E} = -\frac{d\Phi_B}{dt} \]
Ina:
– \( \mathcal{E} \) shine EMF da aka haifar (a cikin volts),
– \( \Phi_B \) shine kwararar maganadisu (a cikin webers),
– \( \frac{d\Phi_B}{dt} \) shine saurin canjin kwararar maganadisu.
Alamar da ba ta da kyau a cikin wannan lissafin ta fito ne daga Dokar Lenz, wadda ta bayyana cewa alkiblar EMF da aka haifar koyaushe tana adawa da canjin kwararar maganadisu da ke haifar da ita.
Juyawar Magnetic
Ruwan maganadisu \( \Phi_B \) ma'auni ne na adadin filin maganadisu da ke ratsawa ta wani yanki. Ana bayyana ruwan maganadisu a matsayin:
\[ \Phi_B = B \cdot A \cdot \cos(\theta) \]
Ina:
– \( B \) shine filin maganadisu (a cikin tesla),
– \( A \) shine yankin da filin maganadisu ya ratsa (a murabba'in mita),
– \( \theta \) shine kusurwar da ke tsakanin filin maganadisu da layin da ke daidai da yankin.
Dokar Lenz
Dokar Lenz ta ba da alkiblar EMF da aka haifar da kuma wutar da ke fitowa. A cewar Dokar Lenz, wutar da aka haifar a cikin da'ira za ta samar da filin maganadisu wanda ke adawa da canjin kwararar maganadisu da ya haifar da shi. A lissafi, ana bayyana wannan ta hanyar alamar mara kyau a cikin lissafin Dokar Faraday.
Gwajin Faraday
Gano Induction na Electromagnetic
Michael Faraday ya gudanar da gwaje-gwaje da dama a shekarar 1831 don yin nazarin alaƙar da ke tsakanin filayen maganadisu da kwararar wutar lantarki. Ɗaya daga cikin manyan gwaje-gwajen Faraday ya haɗa da na'urar waya da aka haɗa da galvanometer (na'urar auna kwararar wutar lantarki) da kuma maganadisu na mashaya. Faraday ya gano cewa lokacin da aka motsa maganadisu na mashaya zuwa ko nesa da na'urar, ana haifar da kwararar wutar lantarki a cikin na'urar, wanda aka gano ta hanyar na'urar galvanometer.
Bambance-bambancen Gwaji
Faraday ya kuma yi wani nau'in gwajin ta amfani da na'urori biyu na waya da aka haɗa a tsakiyar ƙarfe. Lokacin da aka wuce wutar lantarki ta cikin na'urar farko (babban na'urar), filin maganadisu da ya haifar ya haifar da wutar lantarki a cikin na'urar ta biyu (na'urar ta biyu). Faraday ya kammala da cewa canjin filin maganadisu a cikin na'urorin shine sanadin wutar lantarki da aka haifar.
Aiwatar da Dokar Faraday
Janareta Mai Lantarki
Janareta na lantarki yana ɗaya daga cikin manyan aikace-aikacen Dokar Faraday. Janareta suna canza makamashin injiniya zuwa makamashin lantarki ta hanyar ƙa'idar shigar da wutar lantarki. Lokacin da na'urar lantarki ta juya a cikin filin maganadisu, canjin kwararar maganadisu a cikin na'urar yana samar da emf, wanda ke haifar da wutar lantarki.
1. Injin samar da wutar lantarki (AC)
– Ka'idar Aiki: Injin samar da wutar lantarki (AC) yana amfani da filin maganadisu da magnet na dindindin ko electromagnet ke samarwa. Lokacin da na'ura ke juyawa a cikin filin maganadisu, kwararar maganadisu a kan na'urar tana canzawa, tana samar da wutar lantarki mai canzawa.
– Aikace-aikace: Ana amfani da janaretocin AC a manyan tashoshin wutar lantarki, injinan turbine na iska, da janaretocin da ake iya ɗauka.
2. Injin samar da wutar lantarki ta DC (Direct Current)
– Ka'idar Aiki: Injin samar da wutar lantarki na DC yana amfani da na'urar commutator don canza wutar lantarki mai canzawa da ke cikin na'urar zuwa wutar lantarki kai tsaye. Injin commutator na'ura ce ta injiniya wacce ke tabbatar da kwararar wutar lantarki a hanya ɗaya.
– Aikace-aikace: Ana amfani da janareto na DC a aikace-aikace kamar cajin baturi, tsarin wutar lantarki na gaggawa, da aikace-aikacen masana'antu.
Mai canzawa
Na'urar canza wutar lantarki (transformer) wata na'ura ce da ke canza wutar lantarki a tsarin rarraba wutar lantarki, bisa ga ka'idar shigar da wutar lantarki ta hanyar lantarki (electromagnetic induction). Na'urar canza wutar lantarki ta ƙunshi na'urori biyu, na farko da na biyu, waɗanda aka ratsa a kusa da tsakiyar ƙarfe.
– Ka'idar Aiki: Wutar lantarki da ke ratsa ta cikin babban na'urar tana samar da kwararar maganadisu wanda ke haifar da EMF a cikin na'urar ta biyu. Ta hanyar canza adadin juyawa a cikin na'urorin ta farko da ta biyu, ana iya ƙara ko rage ƙarfin lantarki kamar yadda ake buƙata.
– Aikace-aikace: Ana amfani da na'urorin canza wutar lantarki a tsarin rarraba wutar lantarki don ƙara ko rage ƙarfin wutar lantarki, wanda ke ba da damar watsa wutar lantarki cikin inganci daga tashoshin wutar lantarki zuwa ga masu amfani.
Cajin mara waya
Cajin mara waya wata fasaha ce da ke amfani da ƙa'idar shigar da wutar lantarki don canja wurin makamashi ba tare da kebul ba.
– Ka'idar Aiki: Cajin mara waya yana amfani da filin maganadisu da na'urar caji ke samarwa don haifar da EMF a cikin na'urar karɓa da aka haɗa da na'urar da za a caji. Filin maganadisu mai canzawa yana samar da wutar lantarki a cikin na'urar karɓa, wanda ake amfani da shi don cajin batirin na'urar.
– Aikace-aikace: Ana amfani da caji mara waya a cikin na'urorin lantarki kamar wayoyin komai da ruwanka, agogon hannu, da na'urorin likitanci masu ɗaukuwa.
Abubuwan da ke da Alaƙa
1. Tasirin Eddy na Yanzu
– Ka'idar Aiki: Eddy currents sune currents da ke haifar da wutar lantarki a cikin na'urar sarrafawa ta hanyar canjin filin maganadisu. Waɗannan eddy currents suna samar da filin maganadisu wanda ke adawa da canjin kwararar maganadisu da ya haifar da su.
– Aikace-aikace: Ana amfani da wutar lantarki ta Eddy a cikin birki na lantarki, gano ƙarfe, da gwajin da ba ya lalatawa.
2. Magnetoresistance
– Ka'idar Aiki: Magnetoresistance shine canjin juriyar lantarki na wani abu da filin maganadisu na waje ya haifar. Ana amfani da wannan lamari a fasahar adana bayanai da na'urori masu auna maganadisu.
– Aikace-aikace: Ana amfani da Magnetoresistance a cikin rumbun faifai, na'urori masu auna gudu, da tsarin gano matsayi.
3. Tasirin Zaure
– Ka'idar Aiki: Tasirin Hall wani abu ne da ke faruwa inda filin maganadisu da ke daidai da wutar lantarki a cikin na'urar jagora ke haifar da bambancin ƙarfin lantarki a tsakanin na'urar jagora. Ana kiran wannan ƙarfin lantarki da ƙarfin Hall.
– Aikace-aikace: Ana amfani da tasirin Hall a cikin na'urori masu auna maganadisu na Hall don auna filayen maganadisu, gudu, da matsayi.
Aikace-aikacen Fasaha Mai Ci Gaba
Fasaha ta Likitanci: MRI (Hoton Magnetic Resonance Imaging)
MRI wata dabara ce ta daukar hoton likitanci wadda ke amfani da filayen maganadisu da kuma raƙuman rediyo don samar da cikakkun hotuna na tsarin jikin dan adam.
– Yadda Yake Aiki: MRI yana amfani da ƙarfin filin maganadisu don daidaita protons a cikin jiki. Lokacin da aka kunna ko kashe filin maganadisu, waɗannan protons suna fitar da sigina waɗanda kwamfuta ke ɗauka kuma ta sarrafa su zuwa hotuna.
– Aikace-aikace: Ana amfani da MRI don gano cututtuka daban-daban na lafiya, ciki har da ciwace-ciwacen daji, cututtukan zuciya, da cututtukan jijiyoyi. Amfanin MRI shine ikonsa na samar da hotuna masu cikakken bayani ba tare da amfani da hasken ionizing ba.
Motar lantarki
Injinan lantarki suna ɗaya daga cikin aikace-aikacen da aka saba amfani da su a Dokar Faraday wanda ke aiki akan ƙa'idar shigar da wutar lantarki.
– Ka'idar Aiki: Injinan lantarki suna aiki ta hanyar kwararar wutar lantarki ta cikin wani na'ura da ke cikin filin maganadisu, don haka suna samar da ƙarfi wanda ke sa na'urar ta juya.
– Aikace-aikace: Ana amfani da injinan lantarki a cikin na'urori iri-iri, tun daga kayan gida zuwa manyan injinan masana'antu.
Kammalawa
Dokar Faraday ta hanyar amfani da na'urar lantarki (electromagnetic induction) wata ƙa'ida ce ta kimiyya wadda ke bayyana yadda canjin filin maganadisu zai iya samar da wutar lantarki a cikin na'urar jagora. Michael Faraday ya gano wannan doka a shekarar 1831, kuma ta zama tushen fasahohin zamani da yawa, ciki har da janareto na lantarki, na'urorin canza wutar lantarki, da fasahar mara waya. Gwaje-gwajen Faraday sun nuna alaƙar da ke tsakanin filayen maganadisu da wutar lantarki, wanda daga baya aka bayyana shi a lissafi a matsayin dokar shigar da na'urar lantarki.
Amfani da Dokar Faraday yana da faɗi sosai, fannoni kamar samar da wutar lantarki, rarrabawa, caji mara waya, fasahar likitanci, da injinan lantarki. Abubuwan da suka shafi kamar tasirin eddy current, magnetoresistance, da kuma tasirin Hall suna nuna tasirin da ke tattare da shigar da wutar lantarki a kimiyya da fasaha. Yayin da fasaha da bincike ke ci gaba, aikace-aikacen Dokar Faraday za su ci gaba da faɗaɗa, wanda hakan zai buɗe ƙofa ga sabbin abubuwa masu inganci da inganci a nan gaba.
