Thermodynamics Kelvin-Planck statement

Like the engine-based statements, Caratheodory s statement invokes limitations. From a given thermodynamic state of the system, there are states that cannot be reached from the initial state by way of any adiabatic process. We will show that this statement is consistent with the Kelvin-Planck statement of the Second Law. 

An essential step in the Caratheodory formulation of the second law of thermodynamics is a proof of the following statement Two adiabatics (such as a and b in Fig. 6.12) cannot intersect. F rove that a and b cannot intersect. (Suggestion Assume a and b do intersect at the temperature Ti, and show that this assumption permits you to violate the Kelvin-Planck statement of the second law.)... 

Kelvin-Planck statement of the second law of thermodynamics is as follows It is impossible to construct an engine to work in a cyclic process whose sole effect is to convert all the heat supplied to it into an equivalent amount of work. ... 

The second law of thermodynamics dictates that certain processes are irreversible. For example, heat travels in a direction of decreasing temperature. There are two commonly cited equivalent qualitative statements to the second law. The Kelvin-Planck statement states that it is impossible to construct any cyclic device that receives heat from a single thermal reservoir and converts it entirely into work. According to the Clausius statement, it is impossible to construct a device, which operates in a cycle that produces no other effect on the environment other than the transfer of heat from a low temperature reservoir to a higher temperature reservoir. Both of the Kelvin-Planck and Clausius statements of the second... 

The first statement is the Kelvin-Planck statement of the second law of thermodynamics. As a corollary, it is not possible to affect a cyclic process that can convert heat absorbed by a system completely into work done by the system. Mathematically stated, the second law of thermodynamics can be written as... 

The plan of the remaining sections of this chapter is as follows. In Sec. 4.3, a h)q)o-thetical device called a Carnot engine is introduced and used to prove that the two physical statements of the second law (the Clausius statement and the Kelvin-Planck statement) are equivalent, in the sense that if one is true, so is the other. An expression is also derived for the efficiency of a Carnol engine for Ihe purpose of defining thermodynamic temperature. Section 4.4 combines Carnot cycles and the Kelvin-Planck statement to derive the existence... 

The second law of thermod5mamics is stated through the Kelvin-Planck statement and the Clausius statement. The Inequality of Clausius is a consequence of the second law of thermod5mamics, and it is stated for a system undergoing a thermodynamic cycle as... 

Statements of the Second Law Thermodynamic Operation of Heat Engines Kelvin and Planck Statements Temperature Scale Operation of Heat Engines... 

The second law of thermodynamics has historically been a mysterious concept, and the basic idea has been verbalized by Clausius, Kelvin, Planck, and others for those who think in words. One simple statement by Rudolph Clausius (1822-1888) was... 

We begin here the discussion of the Second Law of Thermodynamics. This law has been enunciated in many different forms, the most prominent being the formulations by Kelvin and by Planck. These will be presented later as consequences of the approach derived below. Undoubtedly, the most elegant statement of this Law was provided by Caratheodory in the following form ... 

In most treatises on thermodynamics, it is usual to refer to the laws of thermodynamics. The conservation of energy is referred to as the First La of Thermodynamics, and this principle was discus.sed in detail in Chapter 3. The positivc-dehniie nature of entropy generation used in Chapter 4, or any of the other statements such as those of Clausius or Kelvin and Planck, are referred to as the Second Law of Thermodynamics. The principle of consers ation of mass precedes the development of thermodynamics. and therefore is not considered to be a law of thermodynamics. 

There are several ways of defining the second law of thermodynamics, but a very useful statement, according to Kelvin and Planck, is as follows ... 

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