Mutemo weJoule-Lenz

Emil Khristianovich Lentz (1804 - 1865) - Russian physic physicist. Ndiye mumwe wevaki ve electromechanics. Zita rake rinobatanidzwa nekuwanikwa kwemurairo unotarisa kutungamirirwa kwekuiswa kwemazuva ano, uye mutemo unosarudza magetsi mumutevedzeri anezvino.

Mukuwedzera, Emilie Lenz uye chiFrench physicist Joule, vachidzidza kuongorora zvinokonzerwa nehutachiona hwemazuva ano, pasina mumwe kune mumwe, vakawana mutemo maererano nehuwandu hwehuni hunosunungurwa mumutevedzeri huchave hwakaenzana zvakananga nekona yemagetsi emagetsi anopfuura nepakati pemutungamiri, kupikisa kwaro Uye nguva iyo iyo magetsi inoramba ichichengetedzeka isingachinji muitungamiri.

Uyu mutemo wainzi mutemo weJoule-Lentz, maitiro acho ndeaya:

Q = kl²Rt, (1)

Ikoko Q - chiyero chekupisa kwakabudiswa, l - ikozvino, R - kukonzera kukonzera, t - nguva; Nhamba yekuti k inonzi "thermal yakaenzana nebasa". Nhamba yehuwandu hwehuwandu hunoenderana nesarudzo yezvikamu umo izvo zvakasara zviripo mumutsetse zvinoenzaniswa.

Kana huwandu hwekupisa hunoyerwa mumakorikori, ikozvino mu amperes, kushorwa mu Ohms, uye nguva mumashure, ipapo k inhamba 0.24. Izvi zvinoreva kuti ikozvino mu 1a inopinda mumutungamiri, iyo inopikisa 1 Ohm, mune imwe yechipiri inopisa nhamba, iri 0.24 kcal. Kuenderera mberi kubva pane izvi, chiyero chekupisa mumakorikiti akabudiswa mumutungamiri anogona kuenzaniswa neshoko:

Q = 0.24l²Rt.

Muchigadziro chezvikamu zveS SI, simba, kupisa kwehuwandu uye basa zvakaenzana nemauniti - joules. Nokudaro, kuenzana kwehuwandu hwakakwana mumutemo weJoule-Lenz kubatana. Munyika ino, Joule-Lenz formula ine fomu:

Q = l²Rt. (2)

Mutemo weJoule-Lenz unogona kuvimbiswa nechiitiko. Ikozvino yakapfuura kuburikidza nematare inoputirwa mumvura yakadururirwa mu calorimeter. Ipapo huwandu hwehuni hunosunungurwa mu calorimeter hunoverengwa. Kuvhiringidzwa kwemhepo kunonyatsozivikanwa mberi, ikozvino inotaridzwa nemameterita uye nguva nechigadziro chemasikati. Kuchinja ikozvino mudunhu uye kushandisa micheche yakasiyana, zvinobvira kuongorora mutemo weJoule-Lenz.

Kubva pamutemo we Ohm

I = U / R,

Kuisa parizvino mumashonga (2), tinowana mutsva mutsva wekufanirwa kwemutemo weJoule-Lenz:

Q = (U² / R) t.

Zvakakosha kushandisa shanduko Q = l²Rt kana kuverenga huwandu hwehuni hwakabudiswa mumutambo wekubatanidzwa, nokuti munyaya ino magetsi emagetsi ese anofanana. Saka, apo vatungamiri vakawanda vanobatanidzwa mumaketani, mumwe nomumwe wavo achapiwa huwandu hunopisa hunoenderana nekuramba kwemuitisi. Kana, semuenzaniso, mitambo mitatu yemasikirwo akafanana akabatanidzwa mumakwikwi - mhangura, simbi uye nickel, kupisa kukuru kunogona kubviswa kubva mu nickel, sezvo kubvisa kwayo kwakanyanya, kwakasimba uye kunopisa.

Kana vanofambisa vakabatana, zvino magetsi mavari achave akasiyana, uye magetsi pamagumo evanhu vakadaro vanoita saizvozvo. Kuyera kwehuwandu hwehuni huchasunungurwa pahukama hwakadaro, zviri nani kuitisa, uchishandisa chirevo Q = (U² / R) t.

Iyi sarudzo inoratidza kuti, muhutano hwakafanana, mutungamiriri wega wega achapa huwandu hunopisa sezvo huchave huchienzanisa nehutano hwehutsika.

Kana iwe ukanyatsobatana zvitatu zvakaenzana nhare dzehuni - mhangura, simbi uye nickel - zvakafanana kune imwe uye zvichipfuura ikozvino kuburikidza navo, ipapo huwandu hwekupisa huchabudiswa mumatare emhangura, uye inopisa kupfuura mamwe.

Kutora sechikonzero chemurairo weJoule-Lenz, vanoverenga mitambo yakasiyana-siyana yemagetsi, kupisa uye kupisa magetsi magetsi. Uyewo, kutendeuka kwesimba remagetsi kuva kupisa kunoshandiswa zvikuru.