Abstract
Pedagogically speaking, the formulation of the first law of thermodynamics is the real beginning of the study of heat and energy. Rejecting caloric’s materiality, the mechanical equivalent of heat proved that heat can be measured in terms of mechanical energy and the heat —mechanical energy equivalence led to the first law (the energy conservation principle) and that heat is a form of energy, the lowest-grade form of energy. The conservation principle infers that energy can be neither created nor destroyed, thus, only its form can be transformed. This conceptual understanding and the application of \( dU = \delta Q - pdV \) for thermodynamic processes are two key takeaways of this chapter. The nature of the transformation of energy forms is the outstanding question remaining for further investigation.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
Mechanical energy in the strict sense is kinetic energy and potential energy. The term can also be defined broadly as the form of energy that can be converted to mechanical work completely and directly by an ideal device such as an ideal electric motor. Mechanical energy in this more general sense, therefore, includes electric energy and other forms of energy that can be converted completely into mechanical work.
- 2.
The first law of thermodynamics is the principle that energy is conserved. Although the idea of energy conservation is generally credited to Rumford, Mayer and Joule, the introduction of the internal energy , which was critical in the formulation of the first law, was given by Clausius in 1850. Historically, the first and the second laws were simultaneously formulated by Kelvin and Clausius (this chapter and Chap. 4). For heuristic purpose, the first law is presented first in this chapter.
- 3.
It should be noted that the adiabatic work considered here includes mechanical work (e.g., stirring paddle motion) or electromechanical work leading to gain in the potential energy or/and kinetic energy of the system. The potential and kinetic energy will then be transformed into the internal energy as shown in (22B). Principally, the types of internal energy considered in this book are thermal energy, chemical energy (internal energy in the form of chemical bond), and nuclear energy. Thermal energy is a subset of internal energy . The term heat energy is synonymous with thermal energy.
- 4.
The various definitions of the caloric unit depend on the particular property (specific heat capacity) of water at a given state, in which a particular definition is based.
- 5.
This does not mean that we should abandon calories unit in applied practices, only that it is not required in theoretical physics and engineering fundamentals.
- 6.
“Block universe” was a term introduced by W. James, the pragmatist philosopher. S. Krishnananda in Studies In Comparative Philosophy summarized James’ philosophy,
William James, the great teacher of pragmatism in America, repudiates the claims of the logical reason in constructing systems of absolute monism, which, according to him, gives us an unmanageable “block-universe” and set at naught moral responsibility, free will, effort and aspiration, indeterminacy, want, and struggle which are main characteristics and daily occurrences of life. The pragmatism of William James is a theory of the will which looks with disfavor on the intellectual philosophies that make a self-complete Absolute the entire reality.
S. Krishnananda made this comment on James’ repudiation of the “absolute monism as the entire reality” with the intention to defend the monism of the Absolute. But, James is correct in repudiating monism, reductionism, and block universe.
- 7.
For an excellent introduction to the concept of enthalpy the reader is referred to The Laws of Thermodynamics: A Very Short Introduction by Peter Atkins [4].
- 8.
When heat is absorbed by a system, a change of temperature may or may not take place. For instance, the evaporation of water as a result of heating is not accompanied by temperature change (the constant temperature is called saturation temperature); heat , in this case, is referred to as latent heat . Heating of water without phase change is accompanied by a temperature rise; heat , in this case, is called sensible heat . The processes considered here are heating or cooling processes that produce temperature change in systems.
References
Clausius R (1851) On the moving force of heat, and the laws regarding the nature of heat itself which are deducible therefrom. Philosophical Magazine 2(No. 4):1–21, 102–119 (Translated by J. Tyndall)
Mares JJ et al. (2008) Phenomenological approach to the caloric theory of heat. Thermochimica Acta 474:16–24
Brookes D, Horton G, Van Heuvelen A, Etkina E (2005) Concerning scientific discourse about heat. AIP Conference Proceedings 790:149–152
Atkins P (2010) The Laws of Thermodynamics: A Very Short Introduction. Oxford Univ Press
Coppersmith J (2010) Energy, the Subtle Concept. Oxford Univ Press
Holton G, Brush SG (2001) Physics, the Human Adventure. Rutgers Univ Press (p. 202)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2020 Springer Nature Switzerland AG
About this chapter
Cite this chapter
Wang, LS. (2020). The First Law: The Production of Heat and the Principle of Conservation of Energy. In: A Treatise of Heat and Energy. Mechanical Engineering Series. Springer, Cham. https://doi.org/10.1007/978-3-030-05746-6_3
Download citation
DOI: https://doi.org/10.1007/978-3-030-05746-6_3
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-05745-9
Online ISBN: 978-3-030-05746-6
eBook Packages: EngineeringEngineering (R0)