Kunzwisisa Mutemo waOhm
Dzidzawo zviri mumibvunzo yemuenzaniso wemutemo weOhm uye kukurukura mibvunzo yemutemo weOhm.
Munenge mune zvese zvinofambisa simbi, munda wemagetsi zvakaenzana ne kuwanda kwemagetsi, uko chiyero chemunda wemagetsi nehukuru hwemagetsi chiri chisingachinji. Zvinoratidzwa nemasvomhu kuburikidza ne equation:
ρ = E / J
Tsananguro: E = munda wemagetsi, ρ = resistivity, J = density yemagetsi.
Chinofanana chinoramba chiripo ρ chinonzi resistance chaiyo kana kuti resistivity, kukosha kwayo kuri kuramba kuripo uye hakutsamiri pamagetsi anogadzira magetsi.
Kana munda wemagetsi ukawedzera, huwandu hwemagetsi hunowandawo, zvakasiyana, kana munda wemagetsi ukadzikira, huwandu hwemagetsi hunodzikirawo, zvekuti chiyero chemunda wemagetsi nehukuru hwemagetsi chinoramba chiripo. Ichi chirevo chemutemo weOhm . Saka equation iri pamusoro inotsanangura mutemo weOhm chete kana ρ isingachinji uye isina chekuita nemunda wemagetsi. Mutemo weOhm haushande kana kukosha kweρ kuchichinja kana munda wemagetsi uchichinja.
Zvisinei, zviri nyore kuyera simba remagetsi (V) pane simba remagetsi (E), uye zviri nyorewo kuyera simba remagetsi (I) pane simba remagetsi (J). Nokudaro, kunze kwekunge zvichiratidzwa sesimba remagetsi , simba remagetsi uye resistivity (ρ), mutemo weOhm unoratidzwawo sesimba remagetsi , simba remagetsi uye resistance yemagetsi (R).
Kutanga, funga nezve wire conductor ine urefu (l), cross-sectional area (A) uye pane electric potential difference (V) pakati pemigumo miviri yewaya. Kana electric field yakafanana, inonzi yakafanana mukati mese, saka hukama huripo pakati pe electric field nemusiyano we electric potential unoratidzwa mu equation V = E s ( equation iyi yakakurukurwa mu electric potential material ). Kana electric current density yakafanana mukati mese, zvinoreva kuti hukama huripo pakati pe electric current density ne electric current hunoratidzwa mu equation I = JA ( equation iyi yakakurukurwa mu electric current material ).
Kuti uwane equation inotaura hukama huripo pakati pe electric potential (V), electric current (I) uye electric resistance (R), tsiva E naJ mu resistance equation naE mu equation ye electric potential uye J mu equation ye electric current:
Uyu muenzaniso unotsanangura hukama huripo pakati pesimba remagetsi (V), simba remagetsi (I) uye simba remagetsi (R) mu kondakita. Zvichibva pamuenzaniso uyu, zvinogona kutaurwa kuti simba remagetsi mu kondakita inhamba yemusiyano wesimba remagetsi nesimba remagetsi mu kondakita.
Mutemo weOhm unoti chiyero chemusiyano wesimba remagetsi nemagetsi chinogara kwenguva refu. Nemamwe mashoko, iyi equation inotsanangura mutemo weOhm chete kana resistance yemagetsi (R) iri nguva dzose. Mutemo weOhm haushande kana resistance yemagetsi isiri nguva dzose, kureva kuti, inosiyana.
Mukutsvaga kwe equation iri pamusoro apa, resistance yemagetsi (R) ye conductor ine chekuitawo ne resistance chaiyo (ρ), kureba kwe conductor (l) uye nzvimbo ye cross-sectional (A) ye conductor. Pamasvomhu, izvi zvinoratidzwa mu equation:
Equation iyi inokurukurwa zvakadzama munyaya inotaura nezvekusagadzikana kwemagetsi.
Fomura yeMutemo waOhm
Mutemo weOhm unotsanangurwa nemaequation maviri, anoti ρ = E/J uye R = V/I. Zvinofanira kucherechedzwa kuti maequation maviri aya iOhm's law equation chete kana ρ iri constant uye R iri constant. Kana ρ naR zve conductor zvikachinja, maequation maviri aya haatsananguri mutemo weOhm, asi ρ = E/J inotsanangura kuramba kwakanangana kwe conductor uye R = V/I inotsanangura kuramba kwemagetsi kwe conductor.
Equation ρ = E/J inogona kunyorwa seE = ρ J. Kana ρ iri constant saka E inoenderana zvakananga naJ, zvichireva kuti kana E ikawedzera saka J inowedzera kana kana E ikaderera saka J inoderera.
Saizvozvowo, equation R = V/I inogona kunyorwa seV = I R. Kana R isingachinji, V inoenderana zvakananga naI, zvichireva kuti kana V ikawedzera, ini ndinowedzera, kana kana V ikaderera, ini ndinoderedza.
Zvinhu zvinotevedzera mutemo weOhm zvinonzi iohmic, nepo zvinhu zvisingateereri mutemo weOhm zvichinzi iohmic. Anenge ese maconductor esimbi iohmic, nepo zvimwe zvinhu zvakawanda zvisiri iohmic.
Muzvinhu zvisiri zve-ohmic, kuramba kwemagetsi hakusi nguva dzose, asi kunosiyana zvichienderana nemusiyano wemagetsi neanogona kuitika. Izvi zvinoreva kuti kana magetsi achichinja, kuramba kwechinhu chacho kunochinjawo, uye saizvozvo, kana magetsi achichinja, kuramba kwechinhu chacho kunochinjawo. Nekuti kuramba kwemagetsi kunosiyana, muzvinhu zvisiri zve-ohmic, voltage (V) haina kuenzana zvakananga nemagetsi (I).
Magirafu eV, I uye R
Muzvinhu zveohmic, chiyero cheV kusvika I hachichinji, chinomiririrwa nemutsetse wakatwasuka. Mienzaniso yezvinhu zveohmic isimbi dzinofambisa magetsi. Panguva imwe chete, muzvinhu zvisina ohmic, chiyero cheV kusvika I hachichinji, chinomiririrwa nemutsetse wakakombama. Mienzaniso yezvinhu zvisina ohmic isemiconductor diodes uye transistors.
Mutemo weOhm unoshanda chete pazvinhu zveOhm kwete pazvinhu zvese, saka hazvina kunaka kuudaidza kuti mutemo wakafanana nemutemo waNewton kana mimwe mitemo yefizikisi. Mitemo yefizikisi inoshanda pazvinhu zvese, kwete kune zvimwe zvinhu chete. Zvisinei, kushandiswa kwemutemo weOhm kwave tsika yakajairika, saka uchiri kunzi mutemo weOhm, chero bedzi zvichirangarirwa kuti mutemo weOhm unoshanda chete pazvinhu zveOhm. Kunze kwemutemo weOhm, mumwe muenzaniso wekusanzwisisa kwakajairika ndiko kushandiswa kwemutemo wegesi wakakodzera kana mutemo waHooke.
