Author: haroon
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Physical Interpretation of Internal Energy
Internal energy can be defined as the sum of all the microscopic forms of energy of a system. It is related to the molecular structure and the degree of activities at molecular level and can be viewed as the sum of the kinetic and potential energies of the molecules. Let us consider a system for…
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Internal Energy
Energy exists in various forms such as thermal, mechanical, kinetic, potential, electric, magnetic, chemical, nuclear, etc. In thermodynamics, it is considered that the various forms of energy make up total energy of a system. This total energy can be represented into two groups—macroscopic and microscopic. The macroscopic forms of energy are those a system possesses…
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First Kind of Perpetual Motion Machine (PMM1)
The machine, which would continuously supply mechanical work without some other form of energy disappearing simultaneously, is called first kind of perpetual motion machine (PMM1). PMM1 is impossible. It is a fictitious machine.
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First Law of Thermodynamics
The first law of thermodynamics is equivalent to law of conservation of energy. It deals with the transformation of heat energy into work and vice versa. For closed systems, energy can be transferred by work and heat transfer. In thermodynamics, the term work denotes a means for transferring energy. Work done by a system is considered positive: W >…
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THE FIRST LAW OF THERMODYNAMICS
Mechanical Equivalent of Heat The mechanical equivalent of heat is a concept that has an important part in the development and acceptance of the conservation of energy and the establishment of the science of thermodynamics in the 19th century. The concept stated that motion and heat are mutually interchangeable and that in every case, a given amount…
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Specific Heat at Constant Pressure (Cρ)
The rate of change of enthalpy with respect to absolute temperature when pressure is constant is known as specific heat at constant pressure (Cp). Example 1.1: The property of a substance is given as where u is the specific internal energy (kJ/kg), t is temperature in °C, p is pressure in kN/m2, and v is specific volume (m3/k). Find the Cv and Cp of the substance. Solution:
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IMPORTANT TERMINOLOGIES USED IN THERMODYNAMICS
Thermodynamics: It is the field of thermal engineering that studies the properties of systems that have a temperature and involve the laws that govern the conversion of energy from one form to another, the direction in which heat will flow, and the availability of energy to do work. Mass and Force: Mass is one of the fundamental…
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INTRODUCTION
There are different forms of energy; all the energy cannot be used as a work. The convertibility of energy into work depends on its availability, i.e., how much energy can be converted into useful work. Thermodynamics is a branch of science and engineering that deals with interaction of energy mainly in the forms of heat…
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SUMMARY
Continuing changes in the project management profession and the ways in which projects are managed support a less prescriptive standard. Industry research, global participation with broad industry representation, and an iterative review process shaped and validated the move from a process-based standard to a principle-based standard. Future teams can evaluate the impact of the shift…
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EXPOSURE DRAFT
The draft standard was made available for public review and comment from 15 January to 14 February 2020. Almost 600 individuals submitted comments on the exposure draft. In response to the exposure draft comments, the content was reorganized and edited for clarity. Most comments indicated agreement with the intent of the principle-based standard. The Development…