Lecture 01 Flashcards
Define Macroscopic vs Microscopic behaviours of a physical system.
– Microscopic: Start with equations of
motion of the gas molecules,
consider these statistically, derive
large scale properties - Statistical Mechanics
– Macroscopic. Deal with large scale
properties (e.g. volume of gas,
pressure etc) without considering
microscopic nature - Thermodynamics
Define the Zeroth Law of Thermodynamics.
The 0th Law of Thermodynamics define Temperature: Two systems in equilibrium with a third system are in in thermal equilibrium with each other.
Define the First Law of Thermodynamics.
The 1st Law of Thermodynamics defines Conservation of Energy: Energy can change forms, but is neither created nor destroyed.
Define the Second Law of Thermodynamics.
The 2nd Law of Thermodynamics defines heat flow: Entropy of an isolated system always increases - heat travels from hot objects to cold objects.
Define the Third Law of Thermodynamics.
The 3rd Law of Thermodynamics defines Absolute Zero: Entropy of a system approaches a constant as the temperature approaches absolute zero.
Define System.
A system: The portion of the universe we
select for investigation.
Define Surroundings.
The surroundings: Everything outside the system.
Define Boundary.
The Boundary: What separates the system from
the surroundings.
Define an Open System.
Open systems allow mass in or out (or both);
Energy can enter or leave (or both) an open system.
Define an Adiabetic System
Non-open systems which don’t allow mass in or out (or both);
Energy cannot enter or leave due to adiabatic walls.
Define a Diathermal System
Non-open systems don’t allow mass in or out (or both);
Energy can enter or leave (or both) this system.
