Ma'anar wutar lantarki
A cikin na'urar jagoranci kamar tagulla, akwai electrons waɗanda ke motsawa cikin 'yanci kuma ba zato ba tsammani a cikin babban gudu amma ba sa tserewa daga ƙarfe. Ana kiran electrons waɗanda za su iya motsawa cikin 'yanci electrons. Duk da cewa electrons suna motsawa cikin 'yanci a kowane bangare, babu kwararar electrons a kowace hanya. Wannan yanayin yana faruwa ne lokacin da babu wani bambanci tsakanin ƙarshen waya ta tagulla guda biyu.
Idan aka haɗa wayar da tushen lantarki, akwai yiwuwar bambanci tsakanin ƙarshen waya biyu na jan ƙarfe, don haka ƙirƙirar filin lantarki a cikin wayar jan ƙarfe. Kasancewar filin lantarki yana sa electrons kyauta su fuskanci ƙarfin lantarki F = q E = e E, inda F = ƙarfin lantarki, e = cajin lantarki, E = filin lantarki . Ƙarfin lantarki yana sa duk electrons masu motsi cikin 'yanci su fuskanci hanzari iri ɗaya a cikin alkibla ɗaya da ƙarfin lantarki.
Waɗannan electrons masu kyauta, suna tafiya tare, suna tsakanin atoms masu tsayawa a cikin wayar jan ƙarfe, wanda ke haifar da dukkan electrons su yi karo da waɗannan atoms. Waɗannan karo suna sa electrons masu kyauta su canza alkiblar motsinsu. Duk waɗannan electrons suna ci gaba da fuskantar ƙarfin lantarki, wanda ke sa su hanzarta a daidai alkiblar da ƙarfin lantarki. Bayan sun yi motsi na ɗan lokaci, electrons masu kyauta suna sake haɗuwa da atoms ɗin da ke cikin wayar jan ƙarfe. Duk da haka, electrons masu kyauta koyaushe suna fuskantar ƙarfin lantarki, wanda ke sa duk electrons su sake ƙaruwa.
Don haka, baya ga motsi bazuwar a cikin hanyoyi daban-daban, duk electrons kyauta suna tafiya tare a hankali a cikin alkiblar ƙarfin lantarki da kuma akasin alkiblar filin lantarki. Alkiblar filin lantarki tana daga babban ƙarfin lantarki zuwa ƙaramin ƙarfin lantarki, yayin da electrons ke motsawa daga ƙaramin ƙarfin lantarki zuwa babban ƙarfin lantarki. Motsin bazuwar kowane electron kyauta yana da sauri sosai, yayin da motsi na electrons kyauta a cikin alkiblar ƙarfin lantarki yana da saurin jinkiri sosai. Wannan motsi na electrons kyauta a cikin alkiblar ƙarfin lantarki kuma ana kiransa saurin drift.
Ana bayyana wutar lantarki a matsayin kwararar cajin lantarki ta hanyar wani sashe na mai gudanarwa a wani takamaiman lokaci. Ta hanyar al'ada, alkiblar wutar lantarki iri ɗaya ce da alkiblar motsi na caji mai kyau. An yi wannan yarjejeniya kafin a san cewa abin da ke motsawa a cikin mai gudanarwa electrons ne masu 'yanci, waɗanda aka caji mara kyau. Alkiblar motsin lantarki a cikin mai gudanarwa ya saba da alkiblar wutar lantarki. Saboda haka, lokacin da ake tattaunawa kan kwararar wutar lantarki a cikin mai gudanarwa, abin da ake nufi shine kwararar caji mai kyau, wanda kuma aka sani da wutar lantarki ta al'ada saboda sakamakon wannan yarjejeniya ne.
Tsarin wutar lantarki
A fannin lissafi, ana bayyana wutar lantarki ta hanyar lissafi:
I = ΔQ / Δt
Bayanin dabara: I = wutar lantarki, ΔQ = adadin cajin lantarki, Δt = tazara tsakanin lokaci.
Naúrar wutar lantarki
Naúrar cajin lantarki ita ce Coulomb, naúrar lokaci ita ce ta biyu, don haka naúrar wutar lantarki ita ce Coulomb/daki. Ana kuma kiran Coulomb/daki Ampere , wanda aka sanya wa suna bayan masanin kimiyyar lissafi na Faransa, Andre Marie Ampere (1775-1836). Ampere 1 = 1 Coulomb / dakika (1 A = 1 C / s). A wata ma'anar, wutar lantarki ta Ampere 1 daidai take da cajin lantarki na Coulomb 1 wanda ke ratsa yankin waya na tsawon dakika 1. Bayan bayyanawa a cikin Amperes, ana kuma bayyana wutar lantarki a cikin milliamperes (1 mA = 10 -3 A), microamperes (1 μA = 10 -6 A), nanoamperes (1 nA = 10 -9 A) ko picoamperes (1 pA = 10 -12 A).
Misali tambaya ta 1:
Wutar lantarki ta Amperes 2 tana gudana ta cikin waya na tsawon daƙiƙa 8. Ka ƙayyade girman cajin da ke ratsawa ta wani wuri da kuma adadin electrons a cikin wannan cajin!
Tattaunawa
An san cewa:
Wutar lantarki (I) = 1 Ampere
Tazarar lokaci (t) = daƙiƙa 2
An tambaya: cajin (Q) da adadin electrons (e)
Amsa:
Tsarin wutar lantarki:
I = Q/t
Bayanin dabara: I = wutar lantarki, Q = cajin lantarki, t = tazara lokaci
Cajin wutar lantarki:
Q = I t = (Ampere 2)(daƙiƙa 8) = Coulombs 16.
Cajin lantarki ɗaya shine 1,6 x 10 -19 Coulombs don haka cajin Coulombs 16 yana da adadin electrons kamar 16 C / 1,6 x 10 -19 Coulombs = 10 x 10 electrons 19 .
Wutar lantarki, saurin drift da yawan wutar lantarki
Yi la'akari da cajin mai kyau yana motsawa zuwa dama tare da saurin juyawa v a cikin alkiblar filin lantarki E a cikin mai jagora tare da yankin giciye-sashe A. Cajin mai kyau yana motsawa nesa s = vt a cikin tazara ta lokaci t.
Idan adadin barbashi da aka caji a kowace girma (yawan barbashi da aka caji) n ne kuma girman mai gudanarwa shine A s = A vt, to adadin barbashi da aka caji a cikin girman mai gudanarwa shine n A v t. Idan kowane barbashi da aka caji yana da caji na q to adadin cajin da ke ratsa ƙarshen mai gudanarwa a lokacin tazara t shine Q = nq A v t. Don haka wutar lantarki da ke gudana ta ƙarshen mai gudanarwa shine I = Q/t = nq A v. Yayin da yawan halin yanzu ko halin yanzu a kowane yanki na giciye A shine J = I/A = nq v. Za a iya kammala da cewa kwararar da ke gudana a cikin mai gudanarwa sakamakon ninka yawan barbashi da aka caji (n), girman cajin kowane barbashi (q), yankin giciye na mai gudanarwa (A) da kuma saurin karkatar da barbashi da aka caji (v).
Yi nazarin matsalar misali mai zuwa don fahimtar bambanci tsakanin saurin kowace ƙwayar cuta da aka caji da kuma saurin duk ƙwayoyin cuta da aka caji.
Misali tambaya ta 2:
Wutar lantarki mai ƙarfi ta Amperes 10 tana gudana a cikin wayar jan ƙarfe tare da yankin giciye na 3 x 10-6 m2Yawan lantarki kyauta shine 8,4 x 1028 electrons/m3Kayyade saurin karkatar da wutar lantarki kyauta!
Tattaunawa
An san cewa:
Wutar lantarki (I) = 10 Ampere
Yankin giciye na waya (A) = 3 x 10-6 m2
Yawan lantarki kyauta (n) = 8,4 x 1028 m-3
Cajin lantarki (q) = 1,6 x 10-19 C
An tambaya: Saurin karkatar da lantarki kyauta (v)
Amsa:
Ana ƙididdige saurin electrons ta amfani da dabarar da aka samo a baya:
Bayani: I = wutar lantarki, n = yawan barbashi da aka caji = yawan electrons kyauta, q = cajin electron guda ɗaya, A = yankin giciye na jagorar, v = saurin karkatar da electron
Saurin karkatar da wutar lantarki shine mita 0,248 x 10 -3 /daƙiƙa = milimita 0,248/daƙiƙa.
'Yan lantarki kyauta suna tafiya tare a cikin waya a gudun milimita 0,248 a kowace daƙiƙa. A wata ma'anar, kowace daƙiƙa duk 'yan lantarki kyauta suna motsawa milimita 0,248. Wannan gudu ne mai jinkiri sosai. Idan motsi na 'yan lantarki kyauta yana da jinkiri sosai, me yasa hasken lantarki ke kunnawa nan da nan bayan an kunna maɓallin?
Domin fahimtar wannan, yi la'akari da kwararar electrons a cikin na'urar jagora a matsayin kwararar ruwa a cikin bututu. Idan bututun ya cika da ruwa, to idan an haɗa ƙarshen bututun ɗaya da famfo, ruwa zai fito nan take daga ɗayan ƙarshen. Hakazalika, akwai electrons kyauta a cikin wayar jan ƙarfe da wayar kwan fitila. Lokacin da aka kunna maɓallin, ana samar da filin lantarki tare da saurin kusantar saurin haske (gudun haske = mita 3 x 108 / daƙiƙa), wanda ke sa electrons kyauta su fara tafiya tare nan da nan. Akwai electrons kyauta a cikin wayar kwan fitila, don haka kwan fitilar tana kunnawa nan da nan.
