Lecture 1 Flashcards
What is the first law of thermodynamics?
Energy cannot be created or destroyed, only transformed or transferred.
What is the second law of thermodynamics?
Energy has quality as well as quantity, and actual processes occur in the direction of decreasing quality of energy.
Define system.
A quantity of matter or a region in space chosen for study.
What are the properties of a closed system?
There is a fixed amount of mass and no mass can cross its boundary.
Explain the the difference between intensive and extensive properties.
Intensive - independent of system mass (e.g. temperature, pressure, density)
Extensive - depend on the size of the system
What is equilibrium in thermodynamics?
A state of balance where there are no unbalanced potentials within the system.
What is the state postulate?
The state of a simple compressible system is completely specified by two independent, intensive properties.
Define isothermal processs.
Temperature remains constant.
What is a steady-flow path?
A process during which a fluid flows through a control volume steadily (e.g. turbines, pumps and heat exchangers).
What is a quasistatic/quasi-equilibrium path?
When a process proceeds in such a manner that the system remains infinitesimally close to an equilibrium state at all times.
Define surroundings.
The mass or region outside the system
Define boundary.
The real or imaginary surface that separates the system from its surroundings
Define isobaric process.
Pressure remains constant.
Define isochoric/isometric process.
Specific volume remains constant.
Define cyclic process.
The initial and final states are identical.
