Name: faraday disk dynamo and dc output
Uploaded: 2023-09-18T17:11:16.000Z
Duration: 1 min 23 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

motion-and-stability-forces-and-interactions

Motion and Stability- Forces and Interactions

PS.PSc.6.5

Faraday Disk Dynamo

패러데이 디스크 다이나모는 유도 원리에 따라 작동하는 직류 발전기입니다.
그것은 전도성 샤프트를 통해 일정한 각속도로 회전하는 전도성 디스크로 구성되며, 이는 디스크의 평면에 수직인 균일한 자기장에 배치됩니다. 디스크의 회전은 그 안에서 운동적인 emf를 유도합니다.
속도 벡터가 접하는 디스크의 작은 세그먼트를 생각해 보십시오. 이 세그먼트의 자기력은 방사상 바깥쪽입니다. 이것은 가장자리를 향해 자유 양전하를 축적하고 중앙을 향해 자유 음전하를 축적하여 emf를 초래합니다.
세그먼트 길이의 한계 내에서 emf 방정식을 통합하고 속도 벡터의 크기를 대체하면 운동 emf의 크기가 제공됩니다.
이 디스크는 폐쇄 루프를 가로질러 전류를 전도하는 두 개의 고정 브러시를 통해 회로에 연결할 수 있습니다.
렌츠의 법칙에 따르면 유도 전류는 디스크의 일정한 각속도에 반대합니다. 따라서 디스크가 일정한 각속도로 회전하도록 하기 위한 작업을 수행해야 합니다.

<ol>
	<li>Young, H.D 및 Freedman, RA (2012). 현대 물리학을 가진 대학 물리학. 샌프란시스코, 캘리포니아 : 피어슨. 섹션 29.4, 971페이지.</li>
</ol>

패러데이 디스크 다이나모

패러데이 디스크 발전기는 시간에 따라 일정한 EMF를 생성하는 DC 생성기입니다. 이는 디스크 평면에 수직인 자기장에서 일정한 각속도로 회전하는 전도성 디스크로 구성됩니다. 디스크가 회전하면 자속의 변화가 발생하여 EMF가 발생하고 디스크 가장자리와 중앙에 반대 전하가 발생합니다. 유도된 EMF의 극성은 자기장의 방향과 디스크의 회전 방향에 의해 결정될 수 있습니다. 회전하는 디스크를 브러시를 사용하여 외부 회로에 연결하면 유도 전류가 흐릅니다.

렌츠의 법칙에 따르면 유도된 EMF는 항상 이를 생성하는 원인에 반대됩니다. 패러데이 디스크 발전기의 경우 유도된 EMF는 디스크 회전에 반대됩니다. 따라서 디스크가 일정한 각속도로 회전하도록 하려면 외부 전원을 공급해야 합니다.

이러한 발전기에서 유도된 EMF의 범위는 수 밀리볼트에서 수 볼트에 이릅니다. 유도된 EMF의 크기는 여러 발전기를 직렬로 연결하거나 자기장의 강도, 디스크 반경 및 디스크의 각속도를 증가시킴으로써 더욱 향상될 수 있습니다.

패러데이 디스크 다이나모는 DC 발전기로, 시간이 일정한 emf를 생성합니다. 그것은 일정한 각도로 회전하는 전도성 디스크로 구성됩니다 ...

Education

교육

JoVE Core

Physics

물리학

Unit 1

제1단원

Electromagnetic Induction

전자기 유도

KEY TERMS AND CONCEPTS

주요 용어 및 개념

faraday disk dynamo and dc output

A Faraday disk dynamo is a DC generator that produces an emf constant in time. It uses a conducting disk that spins at constant angular velocity in a magnetic field. The magnetic field is perpendicular to the plane of the disk.

As the disk rotates, the magnetic flux changes and an emf is induced. This causes opposite charges to build up at the rim and at the center of the disk. The direction of the induced emf depends on the direction of the magnetic field and the direction of rotation.

If brushes connect the rotating disk to an external circuit, an induced current flows. Lenz’s law explains that the induced emf opposes the cause that creates it. In this case, the emf opposes the rotation of the disk, so outside power is needed to keep the disk moving at a constant angular velocity.

The induced emf in a Faraday disk dynamo can range from a few millivolts to a few volts. Its size can be increased by connecting multiple generators in series. It can also be raised by using a stronger magnetic field, a larger disk radius, or a faster disk rotation.

Faraday Disk Dynamo and DC Output

induction

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faraday disk dynamo

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key terms and concepts

Learn how a Faraday disk dynamo makes steady DC output, builds charge on the disk, and uses Lenz’s law to resist rotation.

Faraday Disk Dynamo and DC Output | JoVE K12

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Faraday Disk Dynamo and DC Output

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