Загрузил Наталья Семенчук

Магнитные свойства

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Be^ufl 24
Hua-, napa- u ^eppoMamemuKu
Bonpacbi. fluaMarHemu3M. napaMarHemu3M. QeppoMarHemuKu. MarHumHbU
rucmepe3uc. PaGomb CmonemoBa. Towa Kopu.
24.1. fluaMarHemu3M. napaMarHemu3M
B 3aBucuM0CTu om Hucaeiioro 3iaHeiua p Bee BemecTBa MO>I<HO nogeaumt Ha
mpu rpynimi: duaMarHemuKU, napaMarHemuKU u $eppoMarHemuKU. Kak y>i<e
omMeaaaoct, BemecTBa, gaa KomopBix p < 1, ia3BiBaomca guaMariemuKaMu. K HUM
omiocamca BUC- Mym, Megt, pmymt, cepeSpo, 3oaomo, xaop, uiepmiBie ra3Bi u gp.
Cmep^eit u3 TBepgoro guaMariemuKa uau aMnyaa c ^ugKuM (ra3oo6pa3iBiM)
guaMariemuKoM, no\ieineiiBie B ogiopogioe Mariumioe none, ycmaiaBauBaMmca nepneiguKyaapio auiuaM nngyi<nnn nona. B HeogiopogioM MariumioM none Ha
guaMariemuK geficmByem cuaa, Komopaa cmpeMumca BBimoaKiymt ero 3a npegeaBi
nona.
Omiocumeatiaa Mariumiaa nponnnae\iocTB guaMariemuKa aBaaemca Beauauiofi
nocmoaiiofi u He 3aBucum HU om nngyi<nnn Biemiero Mariumioro noaa B0, HU om ycaoBufi Biemien cpegiB (ianpuMep, meMnepamypBi, gaBaeiua u gp.). ^o^moMy
3aBucuMocmt nngyi<nnn Mariumioro noaa B guaMariemuKe om Biemiero Mariumioro
noaa aBaaemca auiefiiofi (puc. 24.1).
^uaMariemu3M cBoficmBeiei BceM Se3 ucKaoaeiua BemecmBaM, io
npoaBaaemca oi moatKo B mex BemecmBax, cyMMapiBifi MariumiBifi MoMeim
amoMoB KomopBix paBei iiygio. Ecau maKoe BemecmBo Biecmu BO Biemiee
Mariumioe noae, mo Ha coScmBeiioe gBu^eiue ^aeKmpoIOB B amoMax
iaKgagBiBaemca gonogiumegtioe gBu^eiue, BBi3Baiioe noaeM. B pe3ygtmame ^mo^o
B Ka^goM u3 amoMoB guaMariemuKa uIgy^upyemca gonoaiumeatiBifi TOK,
Mariumioe noae Komoporo B coomBemcmBuu c npaBuaoM Jleima ianpaBgeio npomuB
Biemiero noaa. ^o^TOMy nngyi<nn>i pe- 3ygtmupyom,ero Mariumioro noaa B
guaMariemuKe B paBia pa3iocmu nngyi<nnn Biemiero noaa B0 u Biympeiiero noaa B':
B = B0 - B'.
npu BBiKaoHeiuu Biemiero Mariumioro noaa uigy^uoiiBie «amoMiBie TOKU»
ucne3aoT, T. e. guaMariemuK pa3MariuHuBaemca.
BemecTBa,
omiocumeatiaa
Mariumiaa
nponnnae\iocTB
BM
KomopBix p> 1, Ha3BiBaomca napaMariemuKaMu. K HUM, B
Hacmiocmu, omio- camca lampufi, Kaaufi, Mariufi, KaatnHH,
Mapraie^ naamuia, pacmBopB ieKomopBx coaen u gp.
O6pa3e^ napaMariemuKa B ogiopogioM BiemieM MariumioM
noae ycmaiaBauBaemca Bgoat auiufi nngyi<nnn ^mo^o noaa. B lePuc. 24.1
1
ogiopogioM MariumioM noae Ha napaMariemuK geficmByem cuaa,
Puc. 24.3
2
Komopaa cmpeMumca Bmaiymt ero B oSaacmt Soaee cuatioro noaa.
Omiocumeatiaa MarHumHaa iiponnnae\iocTt napaMarHemuKoB, KaK
u guaMarHemuKoB, He 3aBucum om BHemHero MarHuTHoro noaa.
no- ^moMy 3aBucuMocmt niigyi<nnn MarHuTHoro noaa
napaMarHemuKa om BHemHero MarHuTHoro noaa maK^e aBaaemca
auiefiiofi (puc. 24.2).
napaMarHemuKaMu aBaaromca Bew,ecmBa, opSumaatitie
Puc. 24.2
Mariumitie MoMeimti amoMoB Komoptix omaunaromca om Hyaa, a
cnuioBtie MarHumHtie MoMeimti amoMoB paBHti iiygio. nog geficmBueM
BHemHero
Mariumioro nona opSumaatitie Mariumitie MoMeimti amoMOB napaMarHemuKa
opuei- mupyromca B ianpaBaeiuu ^mo^o nona. ^o^moMy Biympeiiee MarHUTHoe none
napaMarHemuKa, oSycaoBaeiioe «amoMitiMu moKaMu», ianpaBaeiti B my >i<e
cmopoHy, HTO u Biemiee HaMariuneiioe noae. no ^moH npunuie nngyi<nna
MarHuTHoro noaa B napaMarHemuKe B = B0 + B'. nocKoatKy TenaoBoe gBu^eiue
amoMoB Memaem opu- emaw ux Mariumitix MoMeHmoB B HanpaBaeHuu BHemHero
noaa, mo omiocumeatiaa MarHumHaa npoiinnae\iocTB napaMarHemuKoB
yMeitmaemca c yBeauneiueM meMnepa- mypti. OpaH^y3KUH $U3UK n. Kiopii (18591906) ycmaHaBua, HTO 3aBucuMocmt omiocumeatioH Mariumion iipoiinnae\iocmn
napaMarHemuKoB om meMnepamypti T nog- Huiaromca 3aKoHy
M1
fl
+ T’
(24.1)
rge C - nocmoaiiaa Kiopii.
24.2. OeppoMarHemuKu
0eppoMarHemuKU - ^mo Bew,ecmBa c SoatmuM 3ianeiueM omiocumeatioH
Marium- HOH iipoiinnae\iocmn: M □ 1. K HUM omHocumca HeSoatmaa rpynna
KpucmagauHecKux
TBepgtix mea maKux, KaK ^eae3o, KoSaatm, HuKeat, ieKomoptie pegKo3eMeatHtie
^ae- Meimti, a maK^e pag cnaaBoB. C^e^uaatHO o3gaHHtie cnaaBti, gaa Komoptix M
cocmaBaaem gecamKu mtcan eguiu^ iiaaNBaiom fyeppumaMU. CBoficmBa
$eppoMarae- TUKOB onpegeaaromca HaaunueM B HUX npu omcymcmBuu BHemHero
noaa oSaacmefi caMonpou3BoatHofi (cnoimaHHofi) HaMarHuneHHocmu - doMeHOB.
Ecau B napa- u guaMariemuKax HaMarHuneHHocmt
u3Meia- emca c yBeauneiueM Hanpa^eHHocmu noaa auieHHo,
mo B $ep- poMariemuKax ^ma 3aBucuMocmt Soaee cao^Haa
(puc. 24.3).
y>i<e npu Hanpa^eHHocmu noaa nopagKa 100 AM
HaMarHu- nuBaHue gocmuraem Hactiw,eHua.
^aa ^eppoMariemuKoB xapaKmepio aBaeiue rucmepe3uca.
Puc. 24.3
3
Ecau HeiaMarHuHeHHtifi ^eppoMariemuK noMecmumt BO BHemHee Mariumioe
noae, Komopoe nocaegoBameatio SygeM yBeau- nuBamt om Hyaa go Hj , mo
3aBucuMocmt B = f (H) Btipa3umca
Puc. 24.3
4
KpuBon OA (puc. 24.4), Koropaa ia3biBaerca nepBoiaHantion
unu OCHOBHOH KpUBOH laMariuHuBaiua.
Ecnu iaMariuHuBaiue goBecmu go iacbi^eiua (ronKa A, puc.
24.4), a nocne ^TO^o yMeitmart lanpa^eiiocrt Mariur- Horo nona,
TO u3MeHeHue Mariurion Hiigyi<nHH B Syger npoucxogurt no
KpuBon AD, Koropaa He coBnagaer c AO. npu H = 0
MarHuTHaa ungyi<nu5i uMeer 3iaHeiue OD, Koropoe la3tiBaerca ocraroHion uigy^uen BJfid. ^na roro HTOSM HiigyKHHai
B crana paBHa iiygio, ieoSxoguMo npuno^urt none
npoTHBonono/iaioro HanpaBneHua lanpa^eiiocrtTO H~. ^TO
Puc. 24.4
3iaHeiue lanpa^eiiocru nasNBae'rca KoypuunniGiibiM noneM.
npu gantienmeM yBenuneiuu lanpa^eiiocru nona go -Hj (|)eppo\iarne'im< laMarHururca B nporuBonono^ioM ianpaBneiuu go iacbi^eiua (-Bj ). Ecnu lanpa^eiiocrt
nona cHoBa yMeitmurt go lyna, SygeM iiaoniogaTt ocraroHiyw ui- gyi<nuio (-Bifi6). npu
gantienmeM yBenuneiuu H uigy^ua cHoBa gocrurier 3iaHeiua Bj . 3aMKHyraa KpuBaa
B = f (H) ia3biBaerca nemneu rucmepe3uca. Ecnu (eppoMarieruK noMecrurt B
nepeMeHHoe Mariurioe none, TO u3Meieiue MarHuTHon HiigyKHHH Syger
npoucxogurt B cooTBercTBuu c nernen rucrepe3uca. Pasxiepit nernu rucrepe3uca
3aBucar or roro, B KaKux npegenax u3Meiaerca H. Ecnu 3iaHeiua H ra- Kue, HTO
Bo3HuKaer nacibinenue, nno^agt nernu rucrepe3uca Syger MaKcuMantion. npu
Meitmux 3ianeiuax aMnnurygti KoneSaiun H lacw^eiua He npoucxogur. ner- na
rucrepe3uca, Koropaa npu ^TOM Bo3iuKier, ia3MBaerca nacribiM ^uKnoM. Bepmuit
nacTHbix ^uKnoB pacnonarawrca ia OCHOBHOH KpuBon HaMariunuBaiua (KpuBaa OA,
puc. 24.4). Mariuriaa nponHnae\iocTb (eppoMariuruKa Btipa^aerca (opMynon
(24.2)
OgiaKo no npunuie roro, HTO Me^gy B u H cBa3t Heogio3iaHiaa, noiarue MarHurion npoiiHiiaexiocTH npuMeiawT rontKo gna OCHOBHOK KpuBon
HaMariunuBaiua.
nocKontKy ocioBiaa KpuBaa HaMariunuBaiua OA (puc.
24.4) He aBnaerca npaMon nuiuen, TO Mariuriaa npoiu- nae\iocTt
3aBucur or Hanpa^eiiocru nona H (y, = f (H)) (puc. 24.5).
^na i<a7Kgoro (eppoMarieruKa cy^ecTByer onpegeneiiaa
reMneparypa - mouKa Kiopu (T^), Btme Koropon BemecrBo
repaer (eppoMarinribie cBoncTBa u nepexogur B napaMar- iurioe
cocroaiue. 3aBucuMocrt oriocurention Mariurion
Puc. 24.5
5
nponnnae\iocTn (eppoMariemuka OT meMnepamypBi B okpecmiocmu TOHKU Kopu
onHCNBaeTOi 3ak0H0M IKopii Beiicca:
N
(24.3)
^ = -------- ,
T - TN
rge C - nocmoaiiaa Kopu-Bencca. n. Bence (1865-1940) - (paI^y3CkUH (u3uk,
pa3pa6omHuk (eioMeioioruHeckoH meopuu (eppoMariemu3Ma.
OCIOBBI meopuu (eppoMariumu3Ma pa3pa6omaiBi pyccKUM (U3UKOM ^.H.
OpeikeieM (1894-1952) u ne\ieni<n\i (U3UKOM B. leH3eii6epro\i (1901-1976). OHU
noka3aiu, HTO MariumiBie cBoncTBa (eppoMariemukoB o6ycioBieiBi CHHHOBNMH
MariumiBiMu MoMeimaMu ^IekmpoIOB, HTO npuBogum K Bo3iini<noBennio B
kpucmaiiax Mukpockonuneckux o6iacmen - goMeioB. MariumiBie noia Bcex goMeioB
B kpu- cmaiie opueimupoBaiBi xaomunio, noamoxiy B omcymcmBue Biienniero
Mariumioro noia kpucmaii B neioxi He iaMariuHei.
Eciu o6pa3e^ (eppoMariemuka noMecmumB BO Biemiee Mariumioe none, mo
pa3\iepiB goMeioB, MariumiBie \io\ieiiTBi komopBix opueimupoBaiBi BgoiB noia,
yBeiunuBaomca u3-3a cMew,eiua ux rpaiu^ B pe3yiBmame ^mo^o B (eppoMariemuke
—
B03HUkaem cuiBioe Biympeiie none nngyi<nna komoporo
—► lanpaBieiuo c B' coBnagaem no
nngyi<nneH Biemiero noia B0. Tak kak B' □ B0, mo o6pa3e^ ocmaem- ca laMariuneiiBiM
nocie ciamua Biemiero nona. Ocmamoniaa iaMariuHeiiocmB pa3gnanBi.\
(eppoMariemukoB ieoguiakoBa. MarHumoMmKue (eppoMariemuku, ocma- moniaa
iaMariuHeiiocmB komopBix leBeiuka, ucnoiB3yom B kanecmBe cepgeniukoB
mpaic(opMamopoB u ^gekmpoMa^IumoB, a mak^e locumeien gia 3anucu u xpaieiua
uI(opMa^uu (ayguo, Bugeo, ^BM). MarHumo^ecmKue (eppoMariemuku c 6oiBmon
ocmamonioH iaMariuHeiiocmBM ucnoiB3yom B kanecmBe nocmoaiiBix MariumoB.
6
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