Lub dielectrics nyob rau hauv lub hluav taws xob field

Lub dielectrics nyob rau hauv lub hluav taws xob field ua raws li lawv tej internal qauv. Lawv kuj hu ua uas tsis yog-conductors, txij li thaum, raws li yog lub npe hu, lawv yog cov tshuaj uas tsis tshuam kev hluav taws xob. Lawv tsis muaj free xwb muaj uas yuav muaj peev xwm sawv ntawm tsiv hauv no dielectric.

Cov qauv - yog qhov tsawg tshaj plaws particle ntawm qhov teeb meem uas tseem muaj feem nws tshuaj zog. Nws, nyob rau hauv lem, yog nws tus kheej ua los ntawm atoms nrog lub zoo them nucleus thiab tsis zoo them electrons. Molecule raws li ib tug tag nrho yog nruab nrab. Raws li cov kev tshawb xav covalent bonds tsim nyob rau ntawd ib tug los yog ntau tshaj officers ntawm electrons ua ntau rau combining atoms, molecules muab stability.

Rau txhua hom xwb - zoo (ntxhais) thiab tsis zoo (electrons) - yog ib tug taw tes, uas, raws li nws yog lawv "center ntawm lub ntiajteb txawj nqus" (hluav taws xob). Cov ntsiab lus yog hu ua cov ncej ntawm lub molecule. Nyob rau hauv cov ntaub ntawv uas ib tug qauv ntawm hluav taws xob chaw ntawm lub ntiajteb txawj nqus ntawm opposite nqi: zoo thiab tsis zoo - nws yuav nonpolar (muaj tsis muaj dipole lub sij hawm ntawd).

Tus qauv ntawm lub molecule yuav ua tau asymmetric, piv txwv li, yuav muaj ob txawv atom, ces mus rau ib co raws li offset yuav tsum tshwm sim ntau khub ntawm electrons mus rau ib qho ntawm cov atoms. Kom meej meej, nyob rau hauv cov ntaub ntawv no, lub sis tsis ncaj tis ntawm cov opposite nqi (positive thiab negative) nyob rau hauv lub molecule ua rau mismatch ntawm lawv hluav taws xob chaw ntawm lub ntiajteb txawj nqus. Cov uas ua molecule yog hu ua dawb los yog muaj ib tug dipole lub sij hawm ntawd.

Lub ntsiab khoom teejtug uas yog dielectrics yog lawv muaj peev xwm mus polarize.
Dielectrics yog polarized nyob rau hauv ib tug hluav taws xob field. Qhov no txhais tau tias lawv atoms, cov electrons pib txav raws elongated orbits. Raws li ib tug tshwm sim, ib txhia ntawm lawv nto yog tsis zoo them, lub lwm - zoo. Yog li, ib tug hluav taws xob field nyob rau hauv lub dielectric uas feem hu ua nrog. Uas yog, nyob rau hauv lub electric teb cuam tshuam dielectrics ib txhij (sab hauv thiab sab nraud) uas nyob rau hauv cov ntaub ntawv no yog oppositely qhia.

Cov resultant hluav taws xob field muaj ib lub zog sib npaug zos rau cov sib txawv intensities ntawm lub loj thiab me me teb. Nws yuav tsum tau muab sau tseg hais tias lub teb lub dag lub zog nyob rau hauv lub insulator, txawm yog yus ntawm nws hom, yog ib txwm tsawg tshaj li tus sab nraud hluav taws xob field uas tshwm sim los nws polarization.

Cov kev siv ntawm lub polarization yog nyob rau hauv ncaj qha kev faib ua feem rau cov permittivity ntawm lub dielectric. Tus me nws yog, qhov tsawg sib tshwm sim nyob rau hauv ib tug dielectric polarization thiab lub zog lub electric teb nyob rau ntawd.

Cov nqi tshwm sim tsis tau tsuas yog rau ntawm qhov chaw tab sis kuj nyob rau hauv lub dielectric xaus, tab sis txoj kev hloov thaum nyob rau hauv kev sib cuag nrog lub electrode yog tsis yooj yim sua, vim hais tias cov insulator yog attracted rau lub electrode los ntawm Coulomb rog.

Lub dielectrics nyob rau hauv lub hluav taws xob field yog hais tias nws yog muaj zog, thiab nws yog ua tau rau kom cov kev siv, nyob rau tej qhov tseem ceeb yuav tawg lub zog, i.e. yuav tawg tam sim ntawd los ntawm cov atomic electrons. Qhov no yuav ua rau lub ionization txheej txheem dielectrics, yog li ntawd lawv ua conductors.

Lub magnitude ntawm lwm teb, uas ua rau yus dielectric neej puas, nws yog hu ua lub neej puas voltage. Ib tug coj kev txwv voltage uas tus insulator so - neej puas voltage. Lwm lub npe yog lub npe hu txwv kev nyuaj siab - dielectric zog.

Nws yuav tsum tau muab sau tseg tias tsuas yog tus dielectrics nyob rau hauv lub hluav taws xob field muaj ib tug nrog teb uas tshuam disappears thaum lwm tshem tawm.