Name: hall voltage and charge carriers
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North Carolina K-12 Science Standard Course of Study

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Physical Science

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PS.PSc.6.4

The Hall Effect

Considere un conductor rectangular portador de corriente con electrones como portadores de carga. Cuando se aplica un campo magnético perpendicular al plano del conductor, los electrones que se mueven en línea recta se desplazan debido a la fuerza magnética de desviación.
Los electrones se acumulan en un lado del conductor, dejando el exceso de cargas positivas en el otro lado. Esta separación de carga crea un campo eléctrico dentro del conductor, que ejerce una fuerza eléctrica sobre cada electrón que se opone a la fuerza magnética.
En equilibrio, la magnitud de la fuerza eléctrica equilibra la fuerza magnética, deteniendo la deriva adicional de los electrones. La diferencia de potencial entre los dos lados del conductor es el voltaje pasillo.
Al expresar la velocidad de deriva en términos de corriente, el voltaje Hall también se puede usar para medir la densidad numérica de los portadores de carga.
Las sondas Hall miden la magnitud de un campo magnético desconocido a partir del voltaje Hall y los parámetros conocidos del conductor.
Una aplicación significativa de este descubrimiento es que la polaridad del voltaje Hall implica si los portadores de carga en el conductor son negativos o positivos.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 2. [Versión web]. Recuperado de 514-516 <a href="https://openstax.org/books/university-physics-volume-2/pages/11-6-the-hall-effect">https://openstax.org/books/university-physics-volume-2/pages/11-6-the-hall-effect</a></li>
</ol>

el efecto hall

Edwin H. Hall, en el año 1879, ideó un experimento que podría ser utilizado para identificar la polaridad de los portadores de carga predominantes en un material conductor. Desde una perspectiva histórica, este experimento fue el primero en demostrar que los portadores de carga en la mayoría de los metales son negativos.

<img alt="Figure1" src="/files/ftp_upload/13772/13772_Figure_1.png" style="text-align: center">

Considera una losa de metal de ancho L en un campo magnético constante. Los electrones se mueven de derecha a izquierda, por lo que la fuerza magnética que experimentan empuja a los electrones hacia el borde superior de la losa. Esto deja un exceso de carga negativa en el borde superior de la losa y un exceso de carga positiva en el borde inferior de la losa, lo que resulta en un campo eléctrico dirigido de abajo hacia arriba. La concentración de carga en ambos bordes se acumula hasta que se establece una condición de equilibrio. En el equilibrio, la fuerza eléctrica sobre los electrones en una dirección se equilibra con la fuerza magnética en la dirección opuesta. Esta situación en la que los campos eléctrico y magnético son perpendiculares entre sí se llama situación de campo cruzado.

La corriente en la losa I se puede escribir en términos de la velocidad de deriva vd y el área de la sección transversal de la losa A. La diferencia de potencial entre los bordes de la tira, que también se llama voltaje de Hall, está dado por:

<img alt="Equation1" src="/files/ftp_upload/13772/13772_Equation_1.png" style="text-align: center; height: 40px;"> La polaridad del voltaje de Hall muestra se muestra ya sea los portadores de carga sean positivos o negativos. Otra aplicación importante de este efecto es para materiales con una densidad conocida de portadores de carga. El voltaje de Hall medido puede dar el valor de un campo magnético desconocido. En los laboratorios de investigación en los que los campos de los electro-magnetos utilizados para mediciones precisas deben ser muy estables, se utiliza comúnmente una "sonda Hall" como parte del circuito electrónico para regular el campo.

El Efecto Hall

Edwin H. Hall, en el año 1879, ideó un experimento que podría utilizarse para identificar la polaridad de los portadores de carga predominantes en un ...

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hall voltage and charge carriers

Hall voltage and charge carriers are explained through Edwin H. Hall’s 1879 experiment. His setup helped identify the polarity of the main charge carriers in a conducting material. It also showed, for the first time, that the charge carriers in most metals are negative.

A metal slab is placed in a constant magnetic field. The electrons move from right to left, so the magnetic force pushes them toward the top edge of the slab. This leaves excess negative charge at the top and excess positive charge at the bottom. As a result, an electric field forms from the bottom edge to the top edge.

The charge buildup continues until equilibrium is reached. At that point, the electric force on the electrons balances the magnetic force in the opposite direction. This is called a crossed-field situation because the electric and magnetic fields are perpendicular to each other. The current in the slab, I, can be written in terms of the drift velocity, v d, and the cross-sectional area, A.

The potential difference between the two edges is called the Hall voltage. Its polarity reveals whether the charge carriers are positive or negative. When the density of charge carriers is known, the Hall voltage can also be used to find an unknown magnetic field. In research labs, a Hall probe is often used in electronic circuits to help regulate electromagnet fields so they stay steady for precise measurements.

Hall Voltage and Charge Carriers

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Hall voltage and charge carriers are explained through Edwin H. Hall’s 1879 experiment. His setup helped identify the polarity of the main charge carriers in a conducting material. It also showed, for the first time, that the charge carriers in most metals are negative. A metal slab is placed in a constant magnetic field. The electrons move from right to left, so the magnetic force pushes them toward the top edge of the slab. This leaves excess negative charge at the top and excess positive...

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key terms and concepts

Learn how Hall voltage forms in a magnetic field, how it reveals charge carrier polarity, and how Hall probes help measure and control magnetic fields.

Hall Voltage and Charge Carriers | JoVE K12

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Hall Voltage and Charge Carriers

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