Name: hall voltage and charge carriers
Uploaded: 2025-05-22T09:05:51.000Z
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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.6.4

The Hall Effect

ضع في اعتبارك موصلا مستطيلا يحمل التيار مع الإلكترونات كناقلات شحنة. عندما يتم تطبيق مجال مغناطيسي عموديا على مستوى الموصل ، فإن الإلكترونات تتحرك في انجراف خط مستقيم بسبب القوة المغناطيسية المنحرفة.
تتراكم الإلكترونات على جانب واحد من الموصل ، تاركة شحنات موجبة زائدة على الجانب الآخر. يخلق فصل الشحنة هذا مجالا كهربائيا داخل الموصل ، والذي يمارس قوة كهربائية على كل إلكترون يعارض القوة المغناطيسية.
عند التوازن ، يوازن حجم القوة الكهربائية القوة المغناطيسية ، مما يوقف المزيد من انجراف الإلكترونات. فرق الجهد بين جانبي الموصل هو جهد القاعة.
من خلال التعبير عن سرعة الانجراف من حيث التيار ، يمكن أيضا استخدام جهد القاعة لقياس كثافة عدد ناقلات الشحنة.
تقيس مجسات هول حجم المجال المغناطيسي غير المعروف من جهد القاعة والمعلمات المعروفة للموصل
أحد التطبيقات المهمة لهذا الاكتشاف هو أن قطبية جهد القاعة تشير إلى ما إذا كانت ناقلات الشحنة في الموصل سالبة أم موجبة.

<ol>
	<li>OpenStax. (2019). جامعة الفيزياء المجلد 2. [نسخة الويب]. تم الاسترجاع من 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>

تأثير القاعة

<div style="direction:rtl">ابتكر إدوين ه. هول، في عام 1879، تجربة يمكن استخدامها لتحديد قطبية حاملات الشحنة السائدة في مادة موصلة. ومن الناحية التاريخية، كانت هذه التجربة أول تجربة تثبت أن حاملات الشحنة في معظم المعادن سلبية. <img alt="Figure1" src="/files/ftp_upload/13772/13772_Figure_1.png" style="text-align: center"> تخيل لوحًا معدنيًا عرضه L في مجال مغناطيسي ثابت. تتحرك الإلكترونات من اليمين إلى اليسار، وبالتالي فإن القوة المغناطيسية التي تتعرض لها تدفع الإلكترونات إلى الحافة العلوية من اللوح. وهذا يترك شحنة سالبة زائدة عند الحافة العلوية للبلاطة وشحنة موجبة زائدة عند الحافة السفلية للبلاطة، مما ينتج عنه مجال كهربائي موجه من الأسفل إلى الأعلى. يتزايد تركيز الشحنة عند كلا الحافتين حتى يتم إنشاء حالة التوازن. في حالة التوازن، تتوازن القوة الكهربائية المؤثرة على الإلكترونات في اتجاه واحد مع القوة المغناطيسية في الاتجاه المعاكس. يُسمى هذا السيناريو الذي تكون فيه المجالات الكهربائية والمغناطيسية متعامدة مع بعضها البعض بحالة المجال المتقاطع. يمكن كتابة التيار المار في اللوح I بدلالة سرعة الانجراف، vd، ومساحة المقطع العرضي لـ البلاطة، أ. يُعطى فرق الجهد بين حواف الشريط، والذي يسمى أيضًا بجهد هول، بواسطة، <img alt="Equation1" src="/files/ftp_upload/13772/13772_Equation_1.png" style="text-align: center; height: 40px;"> توضح قطبية جهد هول ما إذا كانت حاملات الشحنة موجبة أم سالبة. تطبيق مهم آخر لهذا التأثير هو للمواد ذات الكثافة المعروفة لحاملات الشحنة. يمكن أن يعطي جهد هول المقاس قيمة مجال مغناطيسي غير معروف. في مختبرات الأبحاث التي يجب أن تكون فيها مجالات المغناطيس الكهربائي المستخدمة لإجراء قياسات دقيقة ثابتة للغاية، يتم استخدام "مسبار هول"؛ يستخدم عادة كجزء من الدائرة الإلكترونية لتنظيم المجال.</div>

ابتكر إدوين إتش هول ، في عام 1879 ، تجربة يمكن استخدامها لتحديد قطبية حاملات الشحنة السائدة في ...

Education

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الفيزياء

Unit 1

الوحدة الأولى

Magnetic Forces and Fields

القوى والمجالات المغناطيسية

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

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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JoVE Core Physics introduces the theory and application of fundamental physics topics, including kinematics, dynamics, fluid mechanics, statics, waves, and acoustics, with concise and easy-to-understand animated videos. Additionally, the scientist-in-action videos demonstrate the application of related concepts in classical and original research experiments performed in today's laboratories worldwide.

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Hall Voltage and Charge Carriers

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