Name: superconductors and magnetic levitation
Uploaded: 2025-05-22T09:05:52.000Z
Duration: 1 min 28 s
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K12 Standards

Virginia  Standards of Learning

HIgh School

Physics

PH.9

PH.9.g

Types Of Superconductors

Quando um ímã permanente é colocado sobre qualquer tipo de material supercondutor, o ímã é repelido e levita em uma posição estável devido ao efeito Meissner. Os supercondutores são categorizados em grupos Tipo I e Tipo II com base em seu comportamento e características.
Os supercondutores do tipo I atuam como condutores quando operados à temperatura ambiente. No entanto, quando resfriado abaixo da temperatura crítica, o movimento molecular dentro da substância é reduzido, permitindo que a corrente flua o mais livremente possível.
Eles normalmente consistem em metais puros como mercúrio, zinco, alumínio, chumbo, etc., e obedecem totalmente ao efeito Meissner, embora tenham um campo magnético crítico baixo.
Os supercondutores do tipo II exibem uma fase intermediária de propriedades comuns e supercondutoras mistas em temperaturas intermediárias e campos acima das fases supercondutoras.
Eles normalmente compreendem nióbio elementar, vanádio, tecnécio e ligas metálicas ou óxidos complexos.
Os supercondutores do tipo II obedecem parcialmente ao efeito Meissner e têm dois campos magnéticos críticos.

<ol>
	<li>OpenStax. (2019). Física Universitária Vol. 2. [Versão Web], Pg 396 - 398. Obtido de <a href="https://openstax.org/books/university-physics-volume-2/pages/9-6-superconductors">https://openstax.org/books/university-physics-volume-2/pages/9-6-superconductors</a></li>
</ol>

tipos de supercondutores

Um supercondutor é uma substância que oferece resistência zero à corrente elétrica quando sua temperatura fica abaixo de um valor crítico. A resistência zero não é o único fenômeno interessante que ocorre quando os materiais atingem suas temperaturas de transição. Um segundo efeito é a exclusão de campos magnéticos, conhecido como efeito Meissner. Um ímã leve e permanente colocado sobre uma amostra supercondutora irá levitar em uma posição estável acima do supercondutor. Trens de alta velocidade que levitam em fortes ímãs supercondutores foram desenvolvidos, eliminando o atrito normalmente experimentado entre o trem e os trilhos. Em 3 de abril de 1997, a linha de teste Yamanashi Maglev, no Japão, foi oficialmente inaugurada e, em abril de 2015, o veículo de teste MLX01 atingiu uma velocidade de 374 mph utilizando fortes ímãs supercondutores.

Os supercondutores podem ser categorizados em supercondutores do Tipo I e do Tipo II.

Trinta metais puros exibem resistividade zero abaixo de sua temperatura crítica e exibem o efeito Meissner, propriedade que exclui campos magnéticos do interior do supercondutor enquanto a temperatura do supercondutor está abaixo de sua temperatura crítica. Esses metais são chamados de supercondutores do Tipo I. A supercondutividade existe apenas abaixo de suas temperaturas críticas e abaixo de determinada intensidade de campo magnético crítico. Os supercondutores do Tipo I possuem aplicações práticas limitadas, pois a intensidade do campo magnético crítico necessária para destruir a supercondutividade é bastante baixa.

Os supercondutores do Tipo II possuem campos magnéticos críticos muito mais altos e podem suportar densidades de corrente muito maiores enquanto permanecem em estado supercondutor. Várias cerâmicas contendo bário-cobre-óxido possuem temperaturas críticas muito mais altas para a transição para o estado supercondutor. Materiais supercondutores que pertencem a essa subcategoria de supercondutores do Tipo II são frequentemente categorizados como supercondutores de alta temperatura.

Tipos de Supercondutores

Um supercondutor é uma substância que oferece resistência zero à corrente elétrica quando cai abaixo de uma temperatura crítica. Resistência zero não é o ...

Education

JoVE Core

Física

Unit 1

Unidade 1

Electromagnetic Induction

Indução Eletromagnética

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

superconductors and magnetic levitation

Superconductors are materials that can carry electric current with zero resistance when they are cooled below a critical temperature. At this point, they also show the Meissner effect, which means they push magnetic fields out of their interior. A light permanent magnet can then levitate in a stable position above the superconducting sample.

This magnetic levitation has real uses. High-speed trains have been built with strong superconducting magnets so they can float above the track and avoid friction. The Yamanashi Maglev test line in Japan opened on April 3, 1997. In April 2015, the MLX01 test vehicle reached 374 mph using strong superconducting magnets.

Superconductors are grouped into Type I and Type II superconductors. Type I superconductors are about thirty pure metals that show zero resistivity below their critical temperature and also display the Meissner effect. They work only below their critical temperature and below a critical magnetic field strength. Because that critical magnetic field is low, Type I superconductors have limited practical use.

Type II superconductors can stay superconducting in much higher magnetic fields. They can also carry much higher current densities while remaining in the superconducting state. Many ceramic superconductors that contain barium-copper-oxide fall into this group. These materials often have much higher critical temperatures, so they are often called high-temperature superconductors.

Superconductors and Magnetic Levitation

induction

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electromagnetic fields

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key terms and concepts

Learn how superconductors show zero resistance, the Meissner effect, and magnetic levitation, then compare Type I and Type II superconductors.

Superconductors and Magnetic Levitation | JoVE K12

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Superconductors and Magnetic Levitation

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