Week 1 (Intro and the First Law) Flashcards
Module Intro and FIrst Law of Thermodynamics)
What is thermodynamics is the study of?
Energy cannot be created or destroyed, but only change from type to another
Thermodynamics is the study of these energy conversion processes.
Energy sources (2)
Capital (finite amount)
e.g atomic energy, fossil fuels, Earth’s energy
Income (not finite as only from sunlight)
e.g Indirect and direct solar radiation
Thermal energy (this is in abundance) can be converted into what?
Mechanical energy (scarce amounts)
System
An identifiable collection of matter, attention focused
Composite System
system, broken down into no. subsystems, for practical reasons
Closed system
surrounded by impermeable barrier
matter cannot enter or leave the system
Isolated system
cannot interact any way, surroundings
every I.system = C.system but not vise versa
e.g test tube insulated, lid, stationary ( no movement, no external heat).
No interaction with system
Property
a measurable characteristic of a system (V, P, mass)
Specific Property
property divided by mass
e.g specific volume, (lower case) v = V / m
V, a property of an actual system
v, a property of a substance
Note that specific property of a substances never changes
Extensive Property
A property whose value for a composite system equals the sum of the values for its subsystem
Intensive Property
A property whose value for a composite system does not equal the sum of the values fro its subsystems
State
state of system at any instance, defined by the values of all its properties at that instance
Phase different
Equilibrium
state where all properties of system, constant
Process
Any change from one equilibrium state to another
Real Process
In moving from one equilibrium state to another, a real process will take system through any no. of non- equilibrium states
