Levitation yog kev kov yeej ntawm lub ntiajteb txawj nqus, uas cov ntsiab lus lossis khoom nyob hauv qhov chaw tsis muaj kev txhawb nqa. Lo lus "levitation" los ntawm Latin Levitas, uas txhais tau tias "lightness".
Levitation yuam kev sib npaug nrog kev ya, vim qhov kawg yog raws huab cua tiv thaiv, uas yog vim li cas noog, kab thiab lwm yam tsiaj ya, thiab tsis txhob levitate.
Levitation hauv physics
Levitation hauv physics hais txog qhov chaw ruaj khov ntawm lub cev hauv thaj chaw gravitational, thaum lub cev yuav tsum tsis txhob kov lwm yam khoom. Levitation hais txog qee qhov tsim nyog thiab nyuaj:
- Ib lub zog uas tuaj yeem cuam tshuam qhov rub thiab lub zog ntawm lub ntiajteb txawj nqus.
- Lub zog uas tuaj yeem ua kom ruaj khov ntawm lub cev hauv qhov chaw.
Los ntawm txoj cai Gauss nws ua raws li hais tias nyob rau hauv ib tug static magnetic teb, static lub cev los yog cov khoom tsis muaj peev xwm ntawm levitation. Txawm li cas los xij, yog tias koj hloov cov xwm txheej, koj tuaj yeem ua tiav levitation.
Quantum Levitation
Cov pej xeem sawv daws tau paub txog quantum levitation nyob rau lub Peb Hlis 1991, thaum ib daim duab nthuav tawm tau luam tawm hauv phau ntawv journal xwm txheej. Nws tau pom tus thawj coj ntawm Tokyo Superconductivity Research Laboratory, Don Tapscott, sawv ntawm lub phaj ceramic superconducting, thiab tsis muaj dab tsi ntawm hauv pem teb thiab phaj. Daim duab tau dhau los ua tiag tiag, thiab lub phaj, uas, nrog rau tus thawj coj sawv ntawm nws, hnyav txog 120 kilograms, tuaj yeem ua rau saum av ua tsaug rau cov nyhuv superconductivity hu ua Meissner-Ochsenfeld effect.
Diamagnetic levitation
Qhov no yog lub npe ntawm hom raug tshem tawm hauv qhov chaw sib nqus ntawm lub cev uas muaj dej, uas nws tus kheej yog lub diamagnet, uas yog, cov khoom uas nws cov atoms muaj peev xwm ua tau hlau nplaum tawm tsam cov kev taw qhia ntawm lub ntsiab electromagnetic. teb.
Nyob rau hauv cov txheej txheem ntawm diamagnetic levitation, lub luag hauj lwm tseem ceeb yog ua los ntawm diamagnetic zog ntawm conductors, uas nws atoms, nyob rau hauv qhov kev txiav txim ntawm ib tug sab nraud magnetic teb, me ntsis hloov qhov tsis muaj zog ntawm electrons nyob rau hauv lawv cov molecules, uas. ua rau cov tsos ntawm ib tug tsis muaj zog magnetic teb opposite nyob rau hauv kev coj mus rau lub ntsiab. Cov nyhuv ntawm qhov tsis muaj zog electromagnetic teb yog txaus los kov yeej lub ntiajteb txawj nqus.
Yuav ua kom pom qhov diamagnetic levitation, cov kws tshawb fawb tau rov ua qhov kev sim ntawm cov tsiaj me.
hom levitation no tau siv rau hauv kev sim ntawm cov khoom muaj sia. Thaum kev sim hauvib qho kev sib nqus sab nraud nrog qhov induction ntawm 17 Tesla, lub xeev ncua (levitation) ntawm qav thiab nas tau ua tiav.
Raws li Newton txoj cai thib peb, cov khoom ntawm cov diamagnets tuaj yeem siv rov ua dua, uas yog, kom levitate cov hlau nplaum hauv thaj chaw ntawm lub diamagnet lossis kom ruaj khov rau hauv qhov chaw electromagnetic.
Diamagnetic levitation yog zoo ib yam nyob rau hauv cov xwm rau quantum levitation. Ntawd yog, nrog rau qhov kev txiav txim ntawm Meissner nyhuv, muaj kev hloov pauv ntawm cov hlau nplaum los ntawm cov khoom ntawm tus neeg xyuas pib. Qhov sib txawv me ntsis yog tias kom ua tiav diamagnetic levitation, xav tau ib qho chaw muaj zog electromagnetic ntau, txawm li cas los xij, nws tsis yog qhov tsim nyog los ua kom txias cov conductors kom ua tiav lawv cov superconductivity, ib yam li cov ntaub ntawv nrog quantum levitation.
Nyob hauv tsev, koj tuaj yeem teeb tsa ntau qhov kev sim ntawm diamagnetic levitation, piv txwv li, yog tias koj muaj ob daim hlau ntawm bismuth (uas yog ib daim diam), koj tuaj yeem teeb tsa cov hlau nplaum nrog qhov qis induction, txog 1 T, nyob rau hauv lub xeev ncua. Tsis tas li ntawd, nyob rau hauv ib qho chaw electromagnetic nrog induction ntawm 11 Tesla, koj tuaj yeem ruaj khov ib lub hlau nplaum me me hauv lub xeev raug tshem tawm los ntawm kev kho nws txoj hauj lwm nrog koj cov ntiv tes, thaum tsis kov cov hlau nplaum txhua.
Ntau zaus cov diamagnets yog yuav luag tag nrho cov inert gases, phosphorus, nitrogen, silicon, hydrogen, nyiaj, kub, tooj liab thiab zinc. Txawm tias tib neeg lub cev yog diamagnetic nyob rau hauv txoj cai electromagnetic teb.
Magnetic levitation
Sib nqus levitation yog qhov ua tau zooib txoj kev lifting ib yam khoom siv magnetic teb. Hauv qhov no, sib nqus siab yog siv los them rau lub ntiajteb txawj nqus thiab lub caij nplooj zeeg dawb.
Raws li Earnshaw's theorem, nws tsis tuaj yeem tuav ib qho khoom hauv qhov chaw gravitational tsis tu ncua. Qhov ntawd yog, levitation nyob rau hauv xws li tej yam kev mob yog tsis yooj yim sua, tab sis yog hais tias peb coj mus rau hauv tus account lub mechanisms ntawm kev txiav txim ntawm diamagnets, eddy currents thiab superconductors, ces zoo levitation yuav ua tau tiav.
Yog tias sib nqus levitation muab nqa nrog kev txhawb nqa tshuab, qhov tshwm sim no hu ua pseudo-levitation.
Meissner effect
Cov nyhuv Meissner yog cov txheej txheem ntawm kev hloov pauv ntawm cov hlau nplaum los ntawm tag nrho cov ntim ntawm tus neeg xyuas pib. Qhov no feem ntau tshwm sim thaum lub sij hawm hloov ntawm tus neeg xyuas pib mus rau lub xeev superconducting. Qhov no yog dab tsi superconductors txawv ntawm qhov zoo tagnrho - txawm tias qhov tseeb tias ob qho tib si tsis muaj kev tiv thaiv, qhov sib nqus induction ntawm cov conductors zoo tagnrho tseem tsis hloov pauv.
Thawj zaug qhov tshwm sim no tau pom thiab piav qhia hauv 1933 los ntawm ob tus kws tshawb fawb German - Meissner thiab Oksenfeld. Tias yog vim li cas quantum levitation qee zaum hu ua Meissner-Ochsenfeld effect.
Los ntawm txoj cai dav dav ntawm electromagnetic teb, nws ua raws li qhov tsis muaj qhov sib nqus hauv qhov ntim ntawm tus neeg xyuas pib, tsuas muaj qhov tam sim no nyob rau hauv nws, uas nyob qhov chaw nyob ze ntawm lub superconductor. Raws li cov xwm txheej no, tus superconductor coj tus cwj pwm zoo ib yam li lub tshuab nqus tsev, thaum tsis yog ib qho.
Cov nyhuv Meissner muab faib ua tag nrho thiab ib nrab, hauvnyob ntawm qhov zoo ntawm superconductors. Tag nrho cov nyhuv Meissner tau pom thaum lub tshav hlau nplaum tawg tag.
High kub superconductors
Muaj ob peb lub superconductors ntshiab hauv qhov xwm txheej. Feem ntau ntawm lawv cov khoom siv superconducting yog alloys, uas feem ntau pom tsuas yog ib feem ntawm Meissner effect.
Nyob rau hauv superconductors, nws yog lub peev xwm ua kom tag nrho cov magnetic teb los ntawm nws cov ntim uas cais cov ntaub ntawv mus rau hauv superconductors ntawm thawj thiab thib ob hom. Superconductors ntawm thawj hom yog cov khoom ntshiab, xws li mercury, lead thiab tin, muaj peev xwm ua kom pom tag nrho Meissner nyhuv txawm nyob rau hauv high magnetic teb. Superconductors ntawm hom thib ob feem ntau yog cov alloys, nrog rau cov ceramics lossis qee cov organic tebchaw, uas, nyob rau hauv cov xwm txheej ntawm cov magnetic teb nrog siab induction, tsuas yog muaj peev xwm ntawm ib feem ntawm qhov chaw sib nqus ntawm lawv lub ntim. Txawm li cas los xij, nyob rau hauv cov xwm txheej ntawm lub zog sib nqus tsis tshua muaj zog, yuav luag txhua tus superconductors, suav nrog hom II, muaj peev xwm ntawm tag nrho Meissner effect.
Ntau pua alloys, tebchaw thiab ntau cov ntaub ntawv ntshiab paub tias muaj cov yam ntxwv ntawm quantum superconductivity.
Mohammed's Coffin Experience
"Mohammed lub hleb" yog hom kev dag nrog levitation. Qhov no yog lub npe ntawm qhov kev sim ua kom pom tseeb qhov tshwm sim.
Raws li cov lus dab neeg Muslim, lub hleb ntawm tus Yaj Saub Mohammed nyob hauv huab cua hauv limbo, tsis muaj kev txhawb nqa thiab kev txhawb nqa. Raws nraimyog li no lub npe ntawm kev paub.
Kev piav qhia ntawm kev paub
Superconductivity tsuas tuaj yeem ua tiav ntawm qhov kub qis heev, yog li lub superconductor yuav tsum tau txias ua ntej, piv txwv li, nrog cov roj kub kub xws li kua helium lossis kua nitrogen.
Tom qab ntawd ib lub hlau nplaum muab tso rau ntawm qhov chaw ntawm lub tiaj tus superconductor. Txawm hais tias nyob rau hauv cov teb uas muaj qhov tsawg kawg nkaus sib nqus induction tsis tshaj 0.001 Tesla, cov hlau nplaum nce siab saum npoo ntawm superconductor li ntawm 7-8 millimeters. Yog tias koj maj mam nce qhov sib nqus lub zog, qhov kev ncua deb ntawm qhov chaw ntawm lub superconductor thiab cov hlau nplaum yuav nce ntxiv.
Cov hlau nplaum yuav txuas ntxiv mus kom txog rau thaum cov xwm txheej sab nraud hloov pauv thiab tus superconductor poob nws cov yam ntxwv superconducting.
