Ukuqonda Amasimu Amagnetic Ezintanjeni Ezithwala Okwamanje
I-Pendahuluan
Amasimu kazibuthe ayisenzakalo semvelo esiye sakhanga abantu amakhulu eminyaka. Enye indlela yokukhiqiza insimu kazibuthe ukudlulisa ugesi ngentambo eqhubayo. Lesi simo saqala ukubonwa nguHans Christian Ørsted ngo-1820, owabonisa ukuthi ugesi ungakhiqiza insimu kazibuthe. Lesi sihloko sizohlola ngokujulile insimu kazibuthe ekhiqizwa yintambo ethwala ugesi, imithetho yayo, kanye nokusetshenziswa kwayo ekuphileni kwansuku zonke.
Ukuqonda Amasimu Kamagnetic kanye Nemibono Eyisisekelo
Insimu yamagnetic yindawo ezungeze imagnethi noma ugesi ogelezayo, okubangela ukuba amandla kazibuthe asebenze kwezinye izinto ezikuleyo nsimu. Le nsimu imelelwa yimigqa yamagnetic field ephuma esigxotsheni sasenyakatho samagnethi bese ingena esigxotsheni saseningizimu samagnethi. Lapho le migqa yamagnetic iseduze, insimu yamagnetic iqina kakhulu.
Uma ugesi ugeleza ku-conductor, njengentambo, udala insimu yamagnetic eyindilinga ezungeze intambo. Isiqondiso sensimu singanqunywa kusetshenziswa umthetho wesandla sokudla, lapho isithupha sesandla sokudla sikhomba khona ohlangothini lwamandla kagesi, kanti eminye iminwe, egobile, ikhombisa isiqondiso sensimu yamagnetic.
Umthetho we-Biot-Savart
Omunye wemithetho eyisisekelo echaza insimu yamagnetic ekhiqizwa ugesi uMthetho we-Biot-Savart. Lo mthetho uqanjwe ngezazi ezimbili zefiziksi zaseFrance, uJean-Baptiste Biot noFélix Savart, abaqala ukuwubhala ekuqaleni kwekhulu le-19.
I-Biot-Savart equation ithi insimu yamagnetic (dB) endaweni ethile ekhiqizwe yi-infinitesimal current element (Idl) yile:
\[ dB = \frac{{\mu_0}}{{4\pi}} \frac{{Idl \times \hat{r}}}{{r^2}} \]
Kuphi:
– \( dB \) iyinsimu yamagnetic encane kakhulu.
– \( \mu_0 \) kuyinto engaguquki yokungena kwe-vacuum, inani layo licishe libe ngu-\( 4\pi \times 10^{-7} \) Tm/A.
– \( I \) ugesi wamanje.
– \( dl \) yingxenye ende yentambo yokuqhuba.
– \( \hat{r} \) iyi-vector yeyunithi yento yamanje ebheke endaweni yokubuka.
– \( r \) ibanga eliphakathi kwento yamanje kanye nephuzu lokubuka.
Kusukela kulesi sibalo, singabona ukuthi insimu yamagnetic ekhiqizwa ugesi ilingana ngqo nobukhulu bombane futhi ilingana ngokuphambene nesikwele sebanga elivela kuntambo.
Umthetho ka-Ampere
Ngaphezu koMthetho we-Biot-Savart, uMthetho ka-Ampère nawo ubalulekile ekuqondeni insimu yamagnetic ezungeze ucingo oluthwala ugesi. Lo mthetho waqala ukwakhiwa ngu-André-Marie Ampère ngo-1826. UMthetho ka-Ampère uthi umugqa ohlanganisiwe wensimu yamagnetic (B) endleleni evaliwe (iluphu) ulingana nomthamo wamandla ogcwele ogeleza kulolophu. Ngokwezibalo, uvezwa kanje:
\[ \iphuzu B \cdot dl = \mu_0 I_{\text{total}} \]
Kuphi:
– \( B \) yinsimu yamagnetic.
– \( dl \) yisici sobude bendlela evaliwe.
– \( I_{\text{total}} \) ugesi ophelele ogeleza endleleni evaliwe.
Umthetho ka-Ampere uwusizo kakhulu ekubaleni amasimu kazibuthe wejometri ezilinganayo njengezintambo eziqondile, ama-solenoid, nama-toroids.
Insimu Kamagnetic Ezungeze Intambo Eqondile Ethwala Ugesi
Entanjeni ende eqondile enogesi \( I \), insimu yamagnetic eyizungezile ingabalwa kusetshenziswa uMthetho ka-Ampere. Ake sithi sikhetha indlela eyindilinga yerediyasi \( r \) ephakathi entanjeni, insimu yamagnetic \( B \) ekude \( r \) kusukela entanjeni izoba njalo kuleyo ndlela. Ngokufaka uMthetho ka-Ampere esikhundleni, sithola:
\[ B \cdot 2\pi r = \mu_0 I \]
Ngakho-ke, insimu yamagnetic ezungeze ucingo oluqondile yile:
\[ B = \frac{{\mu_0 I}}{{2\pi r}} \]
Lokhu kukhombisa ukuthi insimu yamagnetic ilingana nomsinga ogeleza ngentambo futhi ilingana ngokuphambene nebanga elisuka kuntambo.
Insimu Yama-Magnetic Ezungeze I-Solenoid
I-solenoid iyi-coil ende yocingo, ngokuvamile eyi-cylindrical, ekhiqiza insimu enamandla kazibuthe lapho ugesi ugeleza kuyo. Insimu kazibuthe ngaphakathi kwe-solenoid icishe ifane futhi ingabalwa kusetshenziswa uMthetho ka-Ampere. Uma i-solenoid ine-\(n\) turns ngobude beyunithi kanye ne-\(I\) yamandla kagesi igeleza ngentambo, insimu kazibuthe ngaphakathi kwe-solenoid yile:
\[ B = \mu_0 n I \]
Insimu yamagnetic engaphandle kwe-solenoid inganakwa ngoba ibuthakathaka kakhulu uma iqhathaniswa nensimu engaphakathi.
Ukusetshenziswa Kwensimu Kamagnetic Yezintambo Ezithwala Okwamanje
Ukuqonda amasimu kazibuthe akhiqizwa yimisinga kagesi kubalulekile kwezobuchwepheshe eziningi zesimanje:
1. I-Transformer
Ama-Transformer amadivayisi asetshenziselwa ukushintsha i-voltage kagesi. Asebenza ngesimiso sokungeniswa kwe-electromagnetic, lapho insimu kazibuthe eshintshayo ibangela i-voltage entanjeni. I-transformer yakhiwe ngama-coil amabili entambo, eyinhloko kanye neyesibili, azungezwe i-iron core. Lapho ugesi ugeleza nge-coil eyinhloko, insimu kazibuthe ephumayo ibangela i-voltage entanjeni yesibili.
2. AmaMoto Kagesi Namajeneretha
Ama-motor kagesi aguqula amandla kagesi abe amandla omshini esebenzisa isimiso samasimu kazibuthe. Lapho ugesi ugeleza nge-coil yocingo ngaphakathi kwe-motor, insimu kazibuthe ephumayo ixhumana nensimu kazibuthe yomshini oqinile, ikhiqize amandla ajikeleza i-rotor. Ngokuphambene nalokho, i-generator iguqula amandla omshini abe amandla kagesi ngokujikeleza i-coil yocingo ensimini kazibuthe.
3. Ama-Solenoid nama-Electromagnet
Ama-Solenoid asetshenziswa ezinhlotsheni eziningi zokusebenza, njenge-relay, ama-solenoid valve, kanye nama-actuator. Uma ugesi ugeleza nge-solenoid, kukhiqizwa insimu enamandla yamagnetic ngaphakathi kwayo, engasetshenziswa ukuhambisa i-plunger noma enye indlela. Ama-electromagnet angasetshenziswa emishinini yokuphakamisa, ekubhulekeni kwe-electromagnetic, kanye nasemishinini ye-MRI emkhakheni wezokwelapha.
4. Ucingo Olusebenzisa I-Superconducting
Ama-Superconductor ayizinto ezingenakuphikiswa emazingeni okushisa aphansi kakhulu. Uma ugesi ugeleza ngentambo ye-superconducting, ungakha insimu yamagnetic enamandla kakhulu ngaphandle kokulahlekelwa amandla. Lokhu kuwusizo kakhulu kubuchwepheshe be-MRI, ekusheshiseni izinhlayiya, kanye nasekuthuthukisweni kwama-reactor e-nuclear fusion.
Isiphetho
Ukuqonda amasimu kazibuthe akhiqizwa izintambo ezithwala ugesi kuyisisekelo sezinto eziningi kanye nokusetshenziswa kwefiziksi yesimanje. Kusukela emithethweni eyisisekelo efana nemithetho kaBiot-Savart no-Ampère kuya ekubaleni amasimu kazibuthe ngezindlela eziyinkimbinkimbi kakhulu, lezi zimiso zisisiza ukuthuthukisa ubuchwepheshe obuhlukahlukene obushintsha umhlaba. Ngocwaningo oluqhubekayo kanye nokusungula izinto ezintsha kulo mkhakha, singalindela ukubona izinhlelo zokusebenza zobuchwepheshe ezengeziwe ezithembele kumasimu kazibuthe empilweni yansuku zonke.
