Name: thermal equilibrium and the zeroth law
Uploaded: 2025-05-22T09:05:48.000Z
Duration: 1 min 14 s
Channel: JoVE

K12 Standards

Louisiana Student Standards for Science

High School

Chemistry

Energy

HS-PS3-4

Zeroth Law of Thermodynamics

ينص القانون الصفري للديناميكا الحرارية على أنه إذا كان أي جسمين في حالة توازن حراري مع جسم ثالث ، فإنهما أيضا في حالة توازن حراري مع بعضهما البعض.
لفهم هذا تجريبيا ، ضع في اعتبارك ثلاثة أكواب مملوءة بالماء عند ثلاث درجات حرارة مختلفة.
بعد توصيل الدورق A ب و B مع C ، سيتم نقل الحرارة.
بعد فترة من الزمن ، يصل الماء الموجود في الدورق A إلى التوازن الحراري مع الماء الموجود في الدورق B ، ويصل الماء الموجود في الدورق B إلى التوازن مع الماء في الدورق C.
عند تسجيل درجة حرارة الأكواب ، لوحظت درجة حرارة موحدة في جميع الأكواب الثلاثة ، والتي تتوافق مع القانون الصفري للديناميكا الحرارية.
التطبيق الأكثر أهمية للقانون الصفري للديناميكا الحرارية هو الأنواع المختلفة من موازين الحرارة.
عندما يتم استخدام مقياس حرارة لقياس درجة حرارة الجسم ، فإنه يحقق التوازن الحراري عن طريق تغيير درجة حرارته.
وبالتالي ، فإن درجة الحرارة المقاسة للجسم هي في الواقع درجة حرارة مقياس الحرارة.

<ol>
	<li>OpenStax. (2019). جامعة الفيزياء المجلد 2. [نسخة الويب]. تم الاسترجاع من <a href = "https://openstax.org/books/university-physics-volume-2/pages/1-1-temperature-and-thermal-equilibrium">https://openstax.org/books/university-physics-volume-2/pages/1-1-temperature-and-thermal-equilibrium</a></li>
</ol>

القانون الصفري للديناميكا الحرارية

<div style="direction:rtl">تجريبيًا، إذا كان الكائن A في حالة توازن مع الكائن B، وكان الكائن B في حالة توازن مع الكائن C، فإن الكائن A في حالة توازن مع الكائن C. يسمى بيان العبور هذا "قانون الصفر للديناميكا الحرارية". على سبيل المثال، يتم وضع كتلة معدنية باردة وكتلة معدنية ساخنة على لوحة معدنية في درجة حرارة الغرفة. في النهاية، ستكون الكتلة الباردة واللوحة في حالة توازن حراري. بالإضافة إلى ذلك، فإن الكتلة الساخنة واللوحة ستكون في حالة توازن حراري. ومن خلال القانون الصفري يمكننا أن نستنتج أن الكتلة الباردة والكتلة الساخنة في حالة توازن حراري أيضًا. اقترح الفيزيائي البريطاني رالف فاولر الرقم "صفر" في ثلاثينيات القرن العشرين. في ذلك الوقت، تم بالفعل تسمية وترقيم القوانين الأول والثاني والثالث للديناميكا الحرارية. نادرًا ما تم ذكر القانون الصفري، لكنه كان بحاجة إلى مناقشته قبل الآخرين، لذلك أعطاه فاولر رقمًا أصغر. الآن فكر في الحالة التي يكون فيها A مقياس حرارة. يخبرنا القانون الصفري أنه إذا قرأ A درجة حرارة معينة عندما يكون في حالة توازن مع B، ثم تم وضعه على اتصال مع C، فإنه لن يتم تبادل الطاقة مع C؛ وبالتالي فإن قراءة درجة الحرارة ستبقى كما هي. بمعنى آخر، إذا كان جسمان في حالة توازن حراري، فإن لهما نفس درجة الحرارة.</div>

تجريبيا ، إذا كان الكائن A في حالة توازن مع الكائن B ، وكان الكائن B في حالة توازن مع الكائن C ، فإن الكائن A يكون في حالة توازن مع الكائن C.

Education

JoVE Core

Physics

الفيزياء

Unit 1

الوحدة الأولى

Temperature and Heat

درجة الحرارة والحرارة

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

thermal equilibrium and the zeroth law

The zeroth law of thermodynamics explains thermal equilibrium between objects. If object A is in equilibrium with object B, and object B is in equilibrium with object C, then object A is also in equilibrium with object C. This transitive relationship is the key idea behind the law.

A simple example uses metal blocks and a metal plate at room temperature. A cold metal block and a hot metal block are both placed on the plate. Over time, the cold block and the plate reach thermal equilibrium, and the hot block and the plate do too. By the zeroth law, the cold block and the hot block are then also in thermal equilibrium.

The law also helps explain how thermometers work. If a thermometer is in equilibrium with one object and then placed in contact with another object, it will not exchange energy with that object if their temperatures match. Its reading stays the same. In other words, two objects in thermal equilibrium have the same temperature.

The name zeroth law was suggested by British physicist Ralph Fowler in the 1930s. By then, the first, second, and third laws of thermodynamics had already been named. The zeroth law was less often stated, but it had to be discussed before the others, so Fowler gave it the smaller number.

Thermal Equilibrium and the Zeroth Law

temperature and thermal equilibrium

Heat, Temperature, and Everyday Energy

Heat and temperature are key ideas in thermodynamics and in everyday life. People often connect temperature with hot and cold, but science gives it a more precise meaning. Temperature is the quantity measured with a thermometer. It is also linked to the average translational kinetic energy of particles. Heat is different from temperature. Heat is energy that moves from one place or material to another because there is a difference in temperature. That difference in temperature keeps heat...

zeroth law of thermodynamics

The zeroth law of thermodynamics explains thermal equilibrium between objects. If object A is in equilibrium with object B, and object B is in equilibrium with object C, then object A is also in equilibrium with object C. This transitive relationship is the key idea behind the law. A simple example uses metal blocks and a metal plate at room temperature. A cold metal block and a hot metal block are both placed on the plate. Over time, the cold block and the plate reach thermal equilibrium, and...

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key terms and concepts

Learn how the zeroth law of thermodynamics shows that objects in thermal equilibrium have the same temperature and why this matters for thermometers.

Thermal Equilibrium and the Zeroth Law | JoVE K12

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HS-PS3-6

Thermal Equilibrium and the Zeroth Law

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