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

K12 Standards

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North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

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Motion and Stability- Forces and Interactions

PS.PSc.6.5

Faraday Disk Dynamo

La dinamo de disco de Faraday es un generador de corriente continua que funciona según el principio de inducción.
Consiste en un disco conductor que gira con una velocidad angular constante a través de un eje conductor, que se coloca en un campo magnético uniforme perpendicular al plano del disco. La rotación del disco induce una fem de movimiento en él.
Considere un pequeño segmento del disco con un vector de velocidad tangencial a él. La fuerza magnética sobre este segmento es radialmente hacia afuera. Esto acumula cargas positivas libres hacia el borde y cargas negativas libres hacia el centro, lo que resulta en fem.
Integrando la ecuación de la fem dentro de los límites de la longitud del segmento y sustituyendo la magnitud del vector de velocidad se obtiene la magnitud de la fem en movimiento.
Este disco se puede conectar al circuito a través de dos escobillas estacionarias, que conducen la corriente a través del circuito cerrado.
Según la ley de Lenz, la corriente inducida se opone a la velocidad angular constante del disco. Por lo tanto, se debe trabajar para mantener el disco girando a velocidad angular constante.

<ol>
	<li>Young, H.D y Freedman, R.A. (2012). Física Universitaria con Física Moderna. San Francisco, CA: Pearson. Sección 29.4, página 971.</li>
</ol>

dinamo de disco de faraday

Una dinamo de disco de Faraday es un generador de corriente continua, que produce una fuerza electromotriz constante en el tiempo. Consiste en un disco conductor que gira con una velocidad angular constante en un campo magnético, perpendicular al plano del disco. La rotación del disco causa un cambio en el flujo magnético, lo que induce una fuerza electromotriz, haciendo que se desarrollen cargas opuestas en el borde y en el centro del disco. La polaridad de la fuerza electromotriz inducida puede ser determinada por la dirección del campo magnético y la dirección de la rotación del disco. Si el disco giratorio está conectado a un circuito externo mediante cepillos, entonces fluye una corriente inducida. Según la ley de Lenz, la fuerza electromotriz inducida siempre se opone a la causa que la produce. Para la dinamo de disco de Faraday, la fuerza electromotriz inducida se opone a la rotación del disco. Por lo tanto, se debe suministrar energía externa para mantener el disco girando con una velocidad angular constante. La fuerza electromotriz inducida en una dinamo de este tipo puede variar desde unos pocos milivoltios hasta unos pocos voltios. La magnitud de la fuerza electromotriz inducida puede ser mejorada aún más al conectar varios generadores en serie o al aumentar la fuerza del campo magnético, el radio del disco y la velocidad angular del disco.

Dinamo de disco de Faraday

Una dinamo de disco de Faraday es un generador de corriente continua, que produce una fem que es constante en el tiempo. Consiste en un disco conductor que gira ...

Education

Educación

JoVE Core

Physics

Física

Unit 1

Unidad 1

Electromagnetic Induction

Inducción electromagnética

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

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

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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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