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Kelvin s formulation

From the context of the above quotation, similar may be taken to have the same meaning as congruent according to Kelvin s formulation, therefore, the only allowed operations are isometries—transformations in which the distances that separate any two points within the object remain... [Pg.65]

We can now recast the Second Law in a variety of ways. Statement (iv) above provides the basis for Kelvin s Formulation of the Second Law ... [Pg.46]

There are still more recent other formulations of the second law. Kelvin s formulation of the second law is not universally true. It fails for negative absolute temperature states. Of course, most thermodynamic systems do not have such states. However, there are some systems. Therefore, the second law has been reformulated It is impossible to transfer an arbitrarily large amount of heat from a standard heat source with processes terminating at a fixed state of the working system [8]. [Pg.119]

Assuming that H(Y X) < 0 [information variant of Kelvin s formulation of the 11. Principle of Thermodynamics for irreversible cyclical transfer O when the respective relation (34) is valid], we also have the information variant of the second part of Carnot s theorem... [Pg.94]

We are now in a position to recast the second law in a manner frequently adopted in elementary introductions to the second law. Statement (v) above provides the basis for Kelvin s formulation of the second law ... [Pg.66]

It is desirable to find some common measure (preferably a quantitative measure) of the tendency to change and of the direction in which change can occur. In the 1850s, Clausius and Kelvin independently formulated the second law of thermodynamics, and Clausius invented the term entropy S (from the Greek word TpoTT-rj, which means transformation), to provide a measure of the transformational content or the capacity for change. In this chapter, we will develop the properties of this function and its relationship to the direction and extent of natural processes as expressed in the second law of thermodynamics. [Pg.112]

As defined by (4.19) or (4.21), it is easy to recognize that TK is an absolute (strictly non-negative) quantity. Furthermore, one can see from (4.19) that the highest possible efficiency ( —> 1) is achievable only at the absolute zero of the Kelvin scale (7"cK —> 0). In addition, the lowest efficiency of converting heat to work ( —> 0) occurs when the two reservoirs approach the same temperature (7j —> 7"cK), consistent with the statement of Kelvin s principle in Section 4.4. Such limits on engine efficiency can be used to paraphrase the three laws of thermodynamics in somewhat whimsical form as follows (the ultimate formulation of the no free lunch principle) ... [Pg.131]

The theory behind the third law of thermodynamics was initially formulated by Walther Nemst in 1906, which was known as Nemst theorem (https //www.sussex. ac.uk/webteam/gateway/file.php name=a-thermodynamicshistory. pdf site=35). The third law of thermodynamics was conceived from the fact that attaining absolute zero temperature is practically impossible. Lord Kelvin deduced this fact from the second law of thermodynamics with his study of heat transfer, work done, and efficiency of a number of heat engines in series. Kelvin s work was the foundation for the formulation of the third law. It can be stated as follows Absolute zero temperature is not attainable in thermodynamic processes. Another noted scientist, Max Planck, put forward the third law of thermodynamics from his observations in 1913. It states that The entropy of a pure substance is zero at absolute zero temperature. Plank observed that only pure, perfectly crystalline stmctures would have zero entropy at absolute zero temperamre. All other substances attain a state of minimum energy at absolute zero temperature as the molecules of the substance are arranged in their lowest possible energy state. [Pg.87]

The full significance of these observations could not be appreciated in advance of the formulation of the second law of thermodynamics by Lord Kelvin and Clausius in the early 1850 s. In a paper published in 1857 that was probably the first to treat the thermodynamics of elastic deformation, Kelvin showed that the quantity of heat Q absorbed during the (reversible) elastic deformation of any body is related in the following manner to the change with temperature in the work — TFei required to produce the deformation ... [Pg.435]

What kind of solution was expected from physicists As we have seen, many chemists, from Lavoisier on, expected that fundamental chemical problems would be accessible to mathematical solution, meaning not just precise quantification or geometrical explanation but algebraic formulation on mechanical principles. 32 For all the resentment of statements by Kelvin or Boltzmann that chemistry could be reduced to vortex atoms or the kinetics of atoms,33 many nineteenth-century chemists shared Kekule s vague presentiment... [Pg.292]

Notice there is a key difference between Charles s Law and Boyle s Law. While the volume and pressure measurements in Boyle s Law can be measured in any units, as can the volume term in Charles s Law, we do not have this freedom with the temperature. As the relationship is formulated, the temperature must be expressed in kelvins.1 Recall the Kelvin scale starts at absolute zero, the coldest possible temperature. One kelvin is equal to 1°C, and the relationship between the Kelvin scale and the Celsius scale is ... [Pg.131]

I Ecole Polytechnique in 1834. Clapeyron represented Carnot s example of a reversible engine in terms of ap-F diagram (which is used today) and described it with mathematical detail. Clapeyron s article was later read by Lord Kelvin and others who realized the fundamental nature of Carnot s conclusions and investigated its consequences. These developments led to the formulation of the Second Law of thermodynamics as we know it today. [Pg.72]

The origin of the theory of viscoelasticity may be traced to various isolated researchers in the last decades of the nineteenth Century. This early stage of development is essentially due to the work of Maxwell, Kelvin and Voigt who independently studied the one dimensional response of such materials. The linear constitutive relationships introduced therein are the base of rheological models which are still used in many applications [121]. Their works led to Boltzmann s [122] first formulation of three dimensional theory for the isotropic medium, which... [Pg.240]

Yet this observation of the one-way character of spontaneous natural processes is so universal that it is one of the most basic observations of nature. It has been given a name, the second law of thermodynamics, although, historically, it partially precedes the first. Those most important in formulating it were Carnot, Clausius, and Kelvin [2]. Like the first law, Newton s laws, or the law of conservation of matter, it cannot be derived from any more basic law rather, it rests on its ability to explain all the observations ever made to test it. This law appears in many forms and has very far-reaching consequences. Many scientists believe that the second law is the most fundamental of all the laws of nature. [Pg.17]


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