Permittivity

wax polarizability lakabka waxa lagu gartaa qiimo gaar ah, oo la yidhaahdo permittivity dielectric. Tixgeli nooca qiimaha.

U qaadan in xoogga direyska duurka u dhexeeya laba birood lagu eedeeyay in vacuum loo siman yahay si E₀. Haddaba buuxiyo farqiga u dhaxeeya dielectric ah. eedeymaha Electric, oo ka muuqan doontaa at soohdinta u dhaxaysa dielectric iyo kaari ah, sababta oo ah saamaynta kala fogaansho qayb Kipury oogay on taarikada ah. Sida xooga leh ee adag beerta E uu noqdo E₀ yar.

Experience muujinaysaa in markii buuxinta farqiga u dhexeeya taarikada xigta dielectrics siman, xoojinta duurka ku kala duwan yihiin. Sidaa darteed, og xidhiidhka u dhexeeya xoogga duurka korontada ee taarikada ee maqnaanshaha E₀ dielectric iyo E in joogitaanka dielectric ah, waxaa suurtagal ah si loo ogaado polarizability ah, i.e. ay si joogto ah dielectric. tirada waxaa inta badan muujinaysaa by ԑ warqad Giriigga (epsilon). Sidaas awgeed, waxaan soo qori kartaa:

ԑ = E₀ / E.

Permittivity ay muujinaysaa sida ay marar badan xoog berrinka oo ka mid ah xogta amarka in insulator ah (dhqaalaha) in ay ka yar tahay in vacuo.

Yaraynta ciidanka xiriirka ka dhexeeya eedeeyay uu keeno nidaamka kala fogaansho ee dhexdhexaad ah. In beerta koronto, electrons ee atamka iyo taagoo la yareeyo marka la eego udhigo ah, oo waxaa jira daqiiqad Dipole ah. ie kuwa u taagoo in ay leeyihiin xilligan Dipole ah (gaar ahaan u taagoo biyo ah), waxaa u janjeedha duurka koronto. waqti xaadirkaas abuuro ay beerta korontada u gaar ah in counteracts duurka ku ah in uu keeno ay tahay muuqashada. Sidaas darteed, beerta guud korontada waa la dhimay. In beeraha yaryar this ifafaale waxa lagu tilmaamay by fikirka ah si joogto ah dielectric.

Hoos waxaa ku permittivity ee vacuum walxaha:

Air ................................. 1,0006 ....

Shito .............................. .... 2

Plexiglas (Plexiglas) ...... 3-4

Ebonite ................................. .. ... 4

Galaas ................................. .... 7

Glass .............................. .. ...... .4-7

Miikaa ................................. .. ... .4-5

Silk waa dabiici ah ............ 4-5

Baladweyne .............................. 6-7

Amber .............................. ... ...... 12.8

Biyaha .................................... ... ... .81

Qiimayaashan walxaha permittivity tixraac heerkulka gudahood 18-20 ° C. Sidaas darteed, si joogto ah u dielectric ee adkaha ah wax yar ka duwan tahay oo leh heerkulka, ka reeban yihiin ferroelectrics.

On lid ku ah, waxay hoos u gaaska ay sabab u tahay sii kordhaya heerkulka iyo kordhinta ay sabab u tahay culayska sii kordhaya. In dhaqanka, si joogto ah u dielectric hawada loo qaato sida mid ka mid ah.

nijaasta The xaddi yar saamayn yar on heerka cabitaan joogto dielectric.

Haddii laba dhibcood loo aabo yeelin la geeyaa insulator ah, xoojinta berrinka ee ay mid kasta oo ka mid ah eedeymaha ee meesha kharash kale hoos u times ԑ. Laga soo bilaabo tan u socota in ciidamada oo lagu eedeeyay, kuwaas oo la macaamilaan kasta oo kale, sida in times ԑ yar. Sidaa darteed, sharciga Coulomb ee kharashka lagu meeleeyay dielectric la siiyo by:

F = (q₁q₂) / (ԑₐr²).

in unugyada SI :

F = (q₁q₂) / (4πԑₐr²)

halkaas oo F - waa xoog la isdhexgalka, q₁ iyo q₂, - tirada eedeeyay ԑ - waa permittivity waadaxa ah ee dhexdhexaad ah, d - masaafada u dhexeysa eedeeyay dhibic.

Ԑ qiimaha tiro lagu soo bandhigi karaa unugyada aan sabab lahayn (qaraabo qiimaha waadaxa ah ee ԑ₀ vacuum permittivity ah). Qiimaha ԑ = ԑₐ / ԑ₀ yeedhay permittivity qaraabada. Waxaa shaaca inta jeer ee xidhiidhka ka dhexeeya eedeeyay ee ah dhexdhexaad ah oo dhqaalaha koobi karayn waa ka nugul yihiin in vacuum ah; ԑ = ԑₐ / ԑ₀ inta badan loo yaqaan joogto dielectric u adag. Ԑ₀ qiimo tiro, iyo aragti ku xidhan tahay nooca unugyada la doorto; iyo ԑ qiimaha - madax banaan. Sidaas darteed, in habka ԑ₀ esu = 1 (this unit ugu weyn afraad); The permittivity vacuum SI waxaa lagu qeexay by:

ԑ₀ = 1 / (4π˖9˖10⁹) farad / mitir = 8,85˖10⁻¹² f / m (nidaamka this waa ԑ₀ qiimaha derivative).