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Chapter 20

The First Law of Thermodynamics

الأنظمة الديناميكية الحرارية
الأنظمة الديناميكية الحرارية
A thermodynamic system is a set of objects whose thermodynamic properties are of interest. The system is considered to be embedded in its surroundings or ...
العمل المنجز أثناء تغيير الحجم
العمل المنجز أثناء تغيير الحجم
In mechanics, work is done on an object when the force acting on it displaces the object. In thermodynamics, work done on a system can be estimated when ...
المسار بين حالات الديناميكا الحرارية
المسار بين حالات الديناميكا الحرارية
Consider the two thermodynamic processes involving an ideal gas that are represented by paths AC and ABC in Figure 1: In the first process for path A to ...
الحرارة والتمدد الحر
الحرارة والتمدد الحر
The work done by a thermodynamic system depends not only on the initial and final states but also on the intermediate states—that is, on the path. ...
الطاقة الداخلية
الطاقة الداخلية
The internal energy of a thermodynamic system is the sum of the kinetic and potential energies of all the molecules or entities in the system. The kinetic ...
القانون الأول للديناميكا الحرارية
القانون الأول للديناميكا الحرارية
A change in the internal energy of a system depends on the the net heat transfer into the system and the net work done by the system. The first law of ...
القانون الأول للديناميكا الحرارية: حل المشكلات
القانون الأول للديناميكا الحرارية: حل المشكلات
The first law of thermodynamics states that the change in internal energy of the system is equal to the net heat transfer into the system minus the net ...
العمليات الدورية والأنظمة المعزولة
العمليات الدورية والأنظمة المعزولة
A thermodynamic system with zero heat exchange and work is an isolated system. For these systems, the internal energy remains constant. In the case of a ...
العمليات متساوية الحرارة
العمليات متساوية الحرارة
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to ...
العمليات متساوية الضغط ومتساوي الضغط
العمليات متساوية الضغط ومتساوي الضغط
A thermodynamic process that occurs at constant volume is called an isochoric process. According to the first law of thermodynamics, heat supplied or ...
السعات الحرارية للغاز المثالي I
السعات الحرارية للغاز المثالي I
Heat capacity is the ratio of heat absorbed by the substance corresponding to its temperature change. It is also called thermal capacity and the SI unit ...
السعات الحرارية للغاز المثالي II
السعات الحرارية للغاز المثالي II
For a system that undergoes a thermodynamic process at a constant volume condition, the heat absorbed is used only to increase the system's internal ...
السعات الحرارية للغاز المثالي III
السعات الحرارية للغاز المثالي III
The number of independent ways a gas molecule can move along straight line, rotate, and vibrate is called its degrees of freedom. Supposing d represents ...
عمليات ثابتة اللون لغاز مثالي
عمليات ثابتة اللون لغاز مثالي
When an ideal gas is compressed adiabatically, that is, without adding heat, work is done on it, and its temperature increases. In an adiabatic expansion, ...
الضغط والحجم في عملية ثابتة اللون
الضغط والحجم في عملية ثابتة اللون
Free expansion of a gas is an adiabatic process. However, there are few differences between free expansion and adiabatic expansion. During free expansion, ...
العمل المنجز في عملية ثابتة اللون
العمل المنجز في عملية ثابتة اللون
Consider the adiabatic compression of an ideal gas in the cylinder of an automobile diesel engine. The gasoline vapor is injected into the cylinder of an ...
الإمكانات الديناميكية الحرارية
الإمكانات الديناميكية الحرارية
Thermodynamic potentials are state functions that are extremely useful in analyzing a thermodynamic system. They have dimensions of energy. The four ...
علاقات ماكسويل الديناميكية الحرارية
علاقات ماكسويل الديناميكية الحرارية
Maxwell's thermodynamic relations are very useful in solving problems in thermodynamics. Each of Maxwell's relations relates a partial ...
تأثير جول طومسون
تأثير جول طومسون
The Joule-Thomson effect, also known as the Joule-Kelvin effect, describes the temperature change of a fluid when it is forced through a valve or porous ...
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