Ntau yam ntawm lub cev tshwm sim, ob qho tib si microscopic thiab macroscopic, yog electromagnetic nyob rau hauv qhov xwm txheej. Cov no suav nrog lub zog ntawm kev sib txhuam thiab elasticity, tag nrho cov txheej txheem tshuaj, hluav taws xob, hlau nplaum, optics.
Ib qho ntawm qhov tshwm sim ntawm kev sib cuam tshuam ntawm electromagnetic yog qhov txiav txim txav ntawm cov khoom them. Nws yog ib qho tseem ceeb tshaj plaws ntawm yuav luag txhua cov thev naus laus zis niaj hnub no uas tau siv ntau yam - los ntawm lub koom haum ntawm peb lub neej mus rau qhov chaw davhlau.
tswvyim ntawm qhov tshwm sim
Qhov kev txav mus los ntawm cov khoom siv hluav taws xob hu ua hluav taws xob tam sim no. Xws li kev txav mus los ntawm kev them nqi tuaj yeem nqa tawm hauv cov xov xwm sib txawv los ntawm qee qhov hais, qee zaum quasi-particles.
Ib yam yuav tsum tau ua ua ntej rau tam sim no yogprecisely orderly, qhia txav. Cov khoom raug them yog cov khoom uas (nrog rau qhov nruab nrab) muaj thermal chaotic motion. Txawm li cas los xij, qhov tam sim no tshwm sim tsuas yog thaum, tawm tsam keeb kwm yav dhau los ntawm cov txheej txheem kev ntxhov siab tas mus li, muaj kev txav mus los ntawm qee qhov kev taw qhia.
Thaum lub cev txav mus los, hluav taws xob nruab nrab tag nrho, cov khoom hauv nws cov atoms thiab cov molecules, tau kawg, txav mus rau hauv ib qho kev taw qhia, tab sis txij li cov nqi sib txawv hauv cov khoom nruab nrab them rau ib leeg, tsis muaj nqi hloov pauv, thiab peb tuaj yeem tham txog qhov tam sim no tsis muaj txiaj ntsig hauv qhov no.
Yuav ua li cas tam sim no raug tsim
Xav txog qhov yooj yim tshaj plaws ntawm kev txhawb nqa tam sim no. Yog hais tias lub teb hluav taws xob tau siv rau qhov nruab nrab uas cov neeg nqa khoom thauj khoom muaj nyob rau hauv rooj plaub dav dav, qhov kev txiav txim ntawm cov khoom them nqi yuav pib hauv nws. Qhov tshwm sim hu ua tus nqi drift.
Nws tuaj yeem piav qhia luv luv raws li hauv qab no. Ntawm qhov sib txawv ntawm qhov chaw, qhov sib txawv (voltage) tshwm sim, uas yog, lub zog ntawm kev sib cuam tshuam ntawm cov nqi hluav taws xob nyob rau ntawm cov ntsiab lus no nrog lub teb, ntsig txog qhov loj ntawm cov nqi no, yuav txawv. Txij li txhua lub cev lub cev, raws li paub, nyhav rau qhov tsawg kawg nkaus ntawm lub zog muaj peev xwm sib haum xeeb rau lub xeev sib npaug, cov khoom siv hluav taws xob yuav pib txav mus rau qhov sib npaug ntawm qhov muaj peev xwm. Hauv lwm lo lus, daim teb ua qee yam haujlwm los txav cov khoom no.
Thaum lub peev xwm sib npaug, qhov nro ploj mushluav taws xob teb - nws ploj mus. Nyob rau tib lub sijhawm, kev txiav txim txav ntawm cov khoom them nqi, qhov tam sim no, kuj nres. Txhawm rau kom tau txais ib qho chaw ruaj khov, uas yog, lub sijhawm ua haujlwm ywj pheej, nws yog ib qho tsim nyog yuav tsum siv qhov chaw tam sim no, vim tias kev tso tawm ntawm lub zog hauv qee cov txheej txheem (piv txwv li, tshuaj lom neeg), cov nqi sib cais tsis tu ncua thiab pub rau lub zog. ncej, tuav lub hav zoov ntawm hluav taws xob.
Tam sim no tuaj yeem tau txais ntau txoj hauv kev. Yog li, qhov kev hloov pauv hauv qhov chaw sib nqus cuam tshuam rau cov nqi hauv cov khoom siv hluav taws xob nkag mus rau hauv nws thiab ua rau lawv txoj kev taw qhia. Qhov tam sim no hu ua inductive.
Quantitative yam ntxwv ntawm tam sim no
Qhov tseem ceeb ntawm qhov tam sim no tau piav qhia ntau yog lub zog ntawm qhov tam sim no (qee zaum lawv hais tias "tus nqi" lossis yooj yim "tam sim no"). Nws txhais tau tias yog tus nqi hluav taws xob (tus nqi ntawm tus nqi lossis tus nqi ntawm cov nqi qis) dhau ntawm ib lub sij hawm los ntawm ib qho chaw, feem ntau yog los ntawm tus ntoo khaub lig ntawm tus neeg xyuas pib: I=Q / t. Tam sim no ntsuas hauv amperes: 1 A \u003d 1 C / s (coulomb ib ob). Hauv seem ntawm cov hluav taws xob hluav taws xob, lub zog tam sim no ncaj qha ntsig txog qhov sib txawv ntawm qhov sib txawv thiab inversely - mus rau qhov tsis kam ntawm tus neeg xyuas pib: I \u003d U / R. Rau qhov ua tiav Circuit Court, qhov kev cia siab no (Ohm txoj cai lij choj) tau qhia raws li kuv=Ԑ / R + r, qhov twg Ԑ yog lub zog hluav taws xob ntawm qhov chaw thiab r yog nws qhov kev tiv thaiv sab hauv.
Qhov piv ntawm lub zog tam sim no mus rau ntu ntu ntawm tus neeg xyuas pib los ntawm qhov kev txiav txim txav ntawm cov khoom raug them tshwm sim perpendicular rau nws yog hu ua qhov ceev tam sim no: j=I / S=Q/St. Tus nqi no qhia txog tus nqi hluav taws xob uas ntws hauv ib chav tsev ntawm lub sijhawm los ntawm ib cheeb tsam. Qhov siab dua lub zog E thiab hluav taws xob conductivity ntawm nruab nrab σ, qhov ntau dua qhov ceev tam sim no: j=σ∙E. Tsis zoo li lub zog tam sim no, qhov ntau yog vector, thiab muaj kev taw qhia raws li kev txav ntawm cov khoom uas nqa tau tus nqi zoo.
kev taw qhia tam sim no thiab kev tsav tsheb
Hauv thaj chaw hluav taws xob, cov khoom nqa khoom, nyob rau hauv kev cuam tshuam ntawm Coulomb rog, yuav ua rau kev txiav txim txav mus rau tus ncej ntawm qhov tam sim no, tawm tsam hauv kev kos npe ntawm tus nqi. Particles them zoo drift mus rau qhov tsis zoo ncej ("minus") thiab, conversely, dawb tsis zoo nqi yog attracted rau lub "ntxiv" ntawm qhov chaw. Cov khoom tseem tuaj yeem txav mus rau ob qho kev taw qhia ib zaug yog tias muaj cov khoom thauj khoom ntawm ob lub cim hauv qhov nruab nrab.
Rau keeb kwm yog vim li cas, feem ntau lees txais tias tam sim no tau coj mus rau txoj kev tsub nqi zoo - los ntawm "ntxiv" mus rau " rho tawm". Txhawm rau kom tsis txhob muaj kev ntxhov siab, nws yuav tsum nco ntsoov tias txawm hais tias nyob rau hauv feem ntau paub txog tam sim no nyob rau hauv cov hlau conductors, lub zog tiag tiag ntawm hais - electrons - tshwm sim, ntawm chav kawm, nyob rau hauv lub opposite kev taw qhia, no conditional txoj cai ib txwm siv.
kev nthuav tawm tam sim no thiab nrawm nrawm
Feem ntau muaj teeb meem nrog kev nkag siab sai npaum li cas tam sim no txav mus. Ob lub ntsiab lus sib txawv yuav tsum tsis txhob tsis meej pem: qhov ceev ntawm kev nthuav tawm ntawm tam sim no (hluav taws xobteeb liab) thiab lub drift tshaj tawm ntawm hais - them nqa. Thawj yog qhov ceev ntawm qhov kev sib tshuam ntawm electromagnetic kis los yog - uas yog tib yam - lub teb propagates. Nws yog nyob ze (saib rau hauv tus account qhov nruab nrab propagation) mus rau qhov ceev ntawm lub teeb nyob rau hauv lub nqus tsev vacuum thiab yuav luag 300,000 km / s.
Particles ua rau lawv txoj kev txav mus qeeb qeeb (10 -4 –10-3 m / s). Qhov nrawm nrawm yog nyob ntawm qhov kev siv hluav taws xob uas siv hluav taws xob ua rau lawv, tab sis nyob rau hauv txhua rooj plaub nws yog ob peb qhov kev txiav txim ntawm qhov loj me me rau qhov nrawm ntawm thermal random motion ntawm hais (10 5. -106 m/s). Nws yog ib qho tseem ceeb kom nkag siab tias nyob rau hauv qhov kev txiav txim ntawm lub teb, lub simultaneous drift ntawm tag nrho cov dawb nqi pib, yog li tam sim no tshwm sim tam sim ntawd nyob rau hauv tag nrho cov neeg xyuas pib.
Tam sim no
Ua ntej tshaj plaws, cov dej ntws sib txawv los ntawm tus cwj pwm ntawm cov neeg nqa khoom them nyiaj dhau sijhawm.
- Ib qhov tam sim no tsis tu ncua yog qhov tam sim no tsis hloov pauv qhov loj (lub zog) lossis kev taw qhia ntawm cov khoom txav. Qhov no yog txoj hauv kev yooj yim tshaj plaws los txav cov khoom siv hluav taws xob, thiab nws yog qhov pib ntawm txoj kev kawm ntawm hluav taws xob tam sim no.
- Hauv kev hloov tam sim no, cov kev txwv no hloov nrog lub sijhawm. Nws tiam yog raws li qhov tshwm sim ntawm electromagnetic induction uas tshwm sim nyob rau hauv ib tug kaw Circuit Court vim yog ib tug hloov (rotation) ntawm lub magnetic teb. Lub teb hluav taws xob nyob rau hauv rooj plaub no ncua sij hawm thim rov qab siv zog vector. Raws li, cov cim qhia ntawm qhov muaj peev xwm hloov pauv, thiab lawv cov nqi dhau los ntawm "ntxiv" mus rau "tshem tawm" tag nrho cov txiaj ntsig nruab nrab, suav nrog xoom. Raws li qhov tshwm simphenomenon, kev txiav txim txav ntawm cov khoom them nqi hloov kev taw qhia txhua lub sijhawm. Qhov loj ntawm qhov tam sim no hloov pauv (feem ntau yog sinusoidally, uas yog, harmonically) los ntawm qhov siab tshaj plaws mus rau qhov tsawg kawg nkaus. Hloov tam sim no muaj xws li cov yam ntxwv tseem ceeb ntawm qhov ceev ntawm cov oscillations raws li zaus - tus naj npawb ntawm tag nrho cov voj voog ntawm kev hloov ib ob.
Ntxiv rau qhov kev faib tawm tseem ceeb tshaj plaws no, qhov sib txawv ntawm cov dej ntws kuj tuaj yeem ua raws li qhov kev ntsuas raws li qhov xwm txheej ntawm kev txav ntawm cov cab kuj cuam tshuam rau qhov nruab nrab uas tam sim no nthuav tawm.
Kev ua haujlwm tam sim no
Qhov piv txwv nto moo tshaj plaws ntawm qhov tam sim no yog qhov kev txiav txim, qhia txav ntawm cov khoom siv hluav taws xob nyob rau hauv qhov kev txiav txim ntawm hluav taws xob hauv lub cev (nruab nrab). Nws yog hu ua conduction tam sim no.
Hauv cov khoom khib nyiab (hlau, graphite, ntau cov ntaub ntawv nyuaj) thiab qee cov kua (mercury thiab lwm yam hlau melts), electrons yog mobile charged particles. Ib qho kev txav mus los hauv ib tus neeg xyuas pib yog lawv qhov kev cuam tshuam rau cov atoms lossis molecules ntawm cov khoom. Conductivity ntawm hom no yog hu ua hluav taws xob. Hauv cov khoom siv hluav taws xob, cov nqi hloov pauv kuj tshwm sim vim kev txav ntawm cov hluav taws xob, tab sis rau ntau qhov laj thawj nws yooj yim los siv lub tswv yim ntawm lub qhov los piav txog qhov tam sim no - qhov zoo quasiparticle, uas yog qhov txav ntawm electron vacancy.
Hauv cov kev daws teeb meem electrolytic, qhov kev tso tawm tam sim no yog ua tiav vim qhov tsis zoo thiab qhov zoo ions txav mus rau cov ncej sib txawv - cov anode thiab cathode, uas yog ib feem ntawm cov tshuaj.
Hloov tam sim no
Gas - nyob rau hauv ib txwm muaj ib lub dielectric - kuj tuaj yeem dhau los ua tus neeg xyuas pib yog tias raug ionization muaj zog txaus. Gas hluav taws xob conductivity yog sib xyaw. Cov roj ionized twb yog cov ntshav uas ob qho tib si electrons thiab ions, uas yog, tag nrho cov nqi them, txav mus. Lawv qhov kev txiav txim txav mus ua ib qho plasma channel thiab hu ua pa tawm.
Kev taw qhia ntawm kev them nqi tuaj yeem tshwm sim tsis yog hauv ib puag ncig. Piv txwv tias ib lub teeb ntawm electrons los yog ions txav mus rau hauv lub tshuab nqus tsev, tawm ntawm qhov zoo lossis tsis zoo electrode. Qhov tshwm sim no yog hu ua electron emission thiab yog siv dav, piv txwv li, hauv cov khoom siv nqus tsev vacuum. Tau kawg, qhov kev txav no yog qhov tam sim no.
Lwm qhov xwm txheej yog qhov txav ntawm lub cev hluav taws xob macroscopic. Qhov no kuj yog ib qho tam sim no, txij li qhov xwm txheej zoo li no txaus siab rau cov xwm txheej ntawm kev xa nyiaj ncaj qha.
Tag nrho cov piv txwv saum toj no yuav tsum raug suav tias yog kev txiav txim txav ntawm cov khoom them nqi. Qhov tam sim no hu ua convection lossis hloov tam sim no. Nws cov khoom, piv txwv li, sib nqus, zoo ib yam li cov conduction tam sim no.
Kev tsis ncaj ncees tam sim no
Muaj qhov tshwm sim uas tsis muaj dab tsi cuam tshuam nrog kev hloov pauv thiab tshwm sim qhov twg muaj qhov sib txawv ntawm lub sijhawm hluav taws xob uas muaj cov cuab yeej ntawm "tiag" conduction lossis hloov pauv tam sim no: nws ua rau muaj qhov sib nqus sib nqus. Qhov no yogtshwm sim, piv txwv li, nyob rau hauv alternating tam sim no circuits ntawm daim hlau ntawm capacitors. Qhov tshwm sim yog nrog los ntawm kev hloov pauv ntawm lub zog thiab hu ua kev hloov pauv tam sim no.
Qhov tseeb, tus nqi no qhia tau sai npaum li cas cov hluav taws xob hluav taws xob induction hloov ntawm ib qho chaw perpendicular rau cov kev taw qhia ntawm nws vector. Lub tswv yim ntawm hluav taws xob induction muaj xws li lub zog teb thiab polarization vectors. Nyob rau hauv lub tshuab nqus tsev, tsuas yog nro yog coj mus rau hauv tus account. Raws li cov txheej txheem electromagnetic nyob rau hauv cov teeb meem, lub polarization ntawm molecules los yog atoms, nyob rau hauv uas, thaum raug mus rau ib lub teb, lub zog ntawm bound (tsis pub dawb!) tsub nqi, ua rau ib co kev pab cuam rau lub displacement tam sim no nyob rau hauv ib tug dielectric los yog conductor.
Lub npe tau tshwm sim nyob rau xyoo 19th thiab yog qhov xwm txheej, txij li cov hluav taws xob tiag tiag yog kev txiav txim txav ntawm cov khoom siv. Kev hloov pauv tam sim no tsis muaj dab tsi cuam tshuam nrog kev them nqi drift. Yog li ntawd, hais nruj me ntsis, nws tsis yog tam sim no.
Kev tshwm sim (kev ua) ntawm tam sim no
Txoj kev txav ntawm cov khoom them nqi ib txwm nrog qee qhov tshwm sim ntawm lub cev, uas, qhov tseeb, tuaj yeem siv los txiav txim seb cov txheej txheem no puas tshwm sim lossis tsis ua. Nws muaj peev xwm faib cov phenomena (kev ua tam sim no) ua peb pawg:
- Magnetic action. Kev txav hluav taws xob yuav tsum tsim kom muaj qhov sib nqus. Yog tias koj tso lub compass ib sab ntawm tus neeg xyuas pib los ntawm qhov uas tam sim no ntws, lub xub yuav tig mus rau qhov kev taw qhia ntawm qhov tam sim no. Raws li qhov tshwm sim no, cov khoom siv hluav taws xob hluav taws xob ua haujlwm, tso cai, piv txwv li, hloov hluav taws xob hluav taws xobmus rau mechanical.
- cov nyhuv thermal. Qhov tam sim no ua haujlwm kom kov yeej qhov tsis kam ntawm tus neeg xyuas pib, ua rau kev tso tawm ntawm thermal zog. Qhov no yog vim hais tias, thaum lub sij hawm drift, tsub cov khoom muaj kev tawg ntawm cov khoom siv lead ua lattice los yog tus neeg xyuas pib molecules thiab muab lawv lub zog kinetic. Yog hais tias lub lattice ntawm, hais tias, ib tug hlau tau zoo kawg nkaus tsis tu ncua, lub electrons yuav xyaum tsis pom nws (qhov no yog ib tug tshwm sim ntawm lub nthwv dej ntawm cov hais). Txawm li cas los xij, thawj zaug, cov atoms nyob rau hauv qhov chaw lattice lawv tus kheej raug rau thermal vibrations uas ua txhaum nws qhov tsis tu ncua, thiab qhov thib ob, qhov tsis xws ntawm lattice - impurity atoms, dislocations, vacancy - kuj cuam tshuam rau kev txav ntawm electrons.
- Tshuaj ua haujlwm tau pom hauv electrolytes. Cov ions tsis sib haum xeeb, uas cov tshuaj electrolytic dissociated, thaum siv hluav taws xob, raug cais rau cov electrodes, uas ua rau cov tshuaj decomposition ntawm cov electrolyte.
Tshwj tsis yog thaum qhov kev txiav txim ntawm cov khoom them nqi yog qhov kev tshawb fawb ntawm kev tshawb fawb, nws txaus siab rau tus neeg hauv nws cov macroscopic manifestations. Nws tsis yog qhov tam sim no nws tus kheej tseem ceeb rau peb, tab sis cov xwm txheej tau teev tseg saum toj no, uas nws ua rau, vim yog kev hloov pauv ntawm hluav taws xob hluav taws xob mus rau lwm hom.
Txhua yam kev ua tam sim no ua lub luag haujlwm dual hauv peb lub neej. Qee qhov xwm txheej, nws yog ib qho tsim nyog los tiv thaiv tib neeg thiab cov khoom siv los ntawm lawv, hauv lwm tus, tau txais ib qho los yog lwm qhov cuam tshuam los ntawm kev xa mus rau cov nqi hluav taws xob ncaj qha. Lub hom phiaj ntawm ntau yam khoom siv cuab yeej cuab tam.
