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Thermodynamics

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Introduction

Thermodynamics is the area of science that includes the relationship between heat and other kinds of energy. Thermodynamics was discovered and studied beginning in the 1800s. At that time, it was linked to and gained importance because of the use of steam engines.
Historically, thermodynamics developed out of a desire to increase the efficiency of early steam engines, particularly through the work of French physicist Nicolas Leonard Sadi Carnot . Who believed that the efficiency of heat engines was the key that could help France win the Napoleonic Wars.[1] Scottish physicist Lord Kelvin was the first to formulate a concise definition of thermodynamics in 1854.
Thermodynamics is built on the study of energy transfers that can be strictly resolved into two distinct components, heat and work, specified by macroscopic variables.[17] Though thermodynamics originated in the study of cyclic non-equilibrium processes such as the working of heat engines, study of the subject gradually revealed that the notion of heat is inextricably tied to the notion of thermodynamic equilibrium.[18]Thermodynamics is well understood and validated for systems in thermodynamic equilibrium, but as the systems of interest become further and further from thermodynamic equilibrium, their thermodynamical study becomes more and more difficult. Systems in thermodynamic equilibrium have very well experimentally reproducible behaviour, and as interest moves further towards non-equilibrium systems, experimental reproducibility becomes more difficult. The present article takes a gradual approach to the subject, starting with a focus on cyclic processes and thermodynamic equilibrium, and then gradually beginning to further consider non-equilibrium systems.

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Thermodynamics states a set of four laws which are valid for all systems that fall within the constraints implied by each.

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