PHY2023 
Thermal Physics 
202021 

Dr L.A. Correa 


Delivery Weeks: 
T2:0111 

Level: 
5 (NQF) 

Credits: 
15 NICATS / 7.5 ECTS 

Enrolment: 
162 students (approx) 

Description
This module builds on the discussion of thermal properties
in the Stage 1 PHY1024
Properties of Matter module, introduces classical
thermodynamics and shows how its laws arise naturally from the statistical
properties of an ensemble. Realworld examples of the key ideas are presented
and their application in later modules such as
PHY2024 Condensed Matter I and
PHY3070 Stars from Birth to Death
is stressed. The concepts
developed in this module are further extended in the
PHYM001 Statistical Physics module.
Module Aims
The aim of classical thermodynamics is to describe the states and processes of
of systems in terms of macroscopic directly measurable properties. It was largely
developed during the Industrial Revolution for practical purposes, such as improving the
efficiency the steamengines, and its famous three laws are empirically based.
The aim of statistical mechanics, which had major contributions from Maxwell,
Boltzmann and Gibbs, is to demonstrate that statistical methods can
predict the bulk thermal properties of a system from an atomistic description of matter.
The theory provides the only tractable means of analysing the almost unimaginable
complexity of an Nbody system containing 10^{23}
particles. The classical second law of thermodynamics finds a natural explanation
in terms of the evolution of a system from the less probable to the more
probable configurations.
Intended Learning Outcomes (ILOs)
A student who has passed this module should be able to:

Module Specific Skills and Knowledge:
 explain the nature of classical entropy, and its relationship to the second law of thermodynamics;
 determine the maximum efficiency of simple heatengines and heat pumps;
 calculate the equilibrium energy distribution of a system using the Boltzmann distribution;
 explain the origin of the second law from a statistical viewpoint;
 describe the significance of various thermodynamic potentials and deduce relations between them;
 demonstrate, by calculating certain properties of real gases, an understanding of the limitations of the ideal gas law;
 calculate bulk thermodynamic properties such as heat capacity, entropy and free energy from the partition function;
 predict whether a gas constitutes a classical or a quantal gas, and explain key differences in the behaviour of these;

Discipline Specific Skills and Knowledge:
 use calculus to calculate maximum and minimun values of constrained multivariable systems;
 use graphs and diagrams to illustrate arguments and explanations;

Personal and Key Transferable / Employment Skills and Knowledge:
 use a range of resources to develop an understanding of topics through independent study;
 solve problems;
 apply general concepts to a wide range of specfic systems and situations;
 meet deadlines for completion of work for problems classes and develop appropriate
timemanagement strategies.
Syllabus Plan

Introduction
 Brief historical survey.

Basic Thermodynamics
 Temperature: thermodynamic equilibrium and the Zeroth Law; temperature and heat.
 Ideal gases: quasistatic and reversible processes; reversible work.
 Internal energy: adiabatic work; equivalence of work and heat; the First Law.
 Thermal engines: the Second Law; heatengine cycle analysis; Carnot's theorem.
 Entropy: Clausius theorem; entropy; maximumentropy principle.

Advanced Thermodynamics
 Thermodynamic potentials
 Energetic potentials, Legendre transform, Maxwell relations.
 Entropic potentials, physical interpretations, stability.
 Real gases: Joule–Thomson expasion; the van der Waals gas.
 Phase transitions
 Theory of saturated vapours.
 Clapeyron's equations, classification of phase transitions.
 Nernst's postulate: the Third Law; unattainability principle.

Statistical Mechanics
 Boltzmann's principle
 Noninteracting gases, statistical entropy, the partition function.
 Connection with thermodynamics, Boltzmann's factor, the Maxwell–Boltzmann distribution.
 Specific heat: The monoatomic and diatomic ideal gas.
 Quantum gases
 Bose–Einstein and Fermi–Dirac statistics.
 Planck's radiation law, the electrongas model.
Learning and Teaching
Learning Activities and Teaching Methods
Description 
Study time 
KIS type 
22×1hour lectures 
22 hours

SLT 
5×6hour selfstudy packages 
30 hours

GIS 
8×2hour problems sets 
16 hours

GIS 
Problems class support 
8 hours

SLT 
Tutorial support 
3 hours

SLT 
Reading, private study and revision 
71 hours

GIS 
Assessment
Weight 
Form 
Size 
When 
ILOS assessed 
Feedback 
0% 
Exercises set by tutor 
3×1hour sets (typical) 
Scheduled by tutor 
114 
Discussion in tutorials

0% 
Guided selfstudy 
5×6hour packages 
Fortnightly 
114 
Discussion in tutorials

10% 
8 × Problems sets 
2 hours per set 
Weekly 
114 
Marked in problems class, then discussed in tutorials

15% 
Midterm Test 
30 minutes 
Weeks T2:06 
113 
Marked, then discussed in tutorials

75% 
Examination 
120 minutes 
May/June assessment period 
113 
Mark via MyExeter, collective feedback via ELE and solutions. 
Resources
The following list is offered as an indication of the type & level of information that
students are expected to consult. Further guidance will be provided by the Module Instructor(s).
Core text:
Supplementary texts:

Callen H.B. and Callen K. (1960), Thermodynamics: An Introduction to the Physical Theories of Equilibrium Thermostatics & Irreversible Thermodynamics, Wiley, ISBN 0471130354 (UL: 536.7 CAL)

Fermi E. (1956), Thermodynamics, Prentic Hall, ISBN 9780486603612 (UL: eBook)

Mandl F. (1988), Statistical Physics (2^{nd} edition), John Wiley, ISBN 9780471915331 (UL: 530.132 MAN)

Sommerfeld A. (1964), Thermodynamics and Statistical Mechanics, Academic Press, ISBN 0126546800 (UL: 530 SOM)

Zemanski M.W. and Dittman R.H. (1981), Heat and Thermodynamics : An Intermediate Textbook (6^{th} edition), McGrawHill, ISBN 0070728089 (UL: 536.7 ZEM)
ELE:
Further Information
Prior Knowledge Requirements
Prerequisite Modules 
Properties of Matter (PHY1024) and Mathematics for Physicists (PHY1026) 
Corequisite Modules 
Mathematics with Physical Applications (PHY2025) 
Reassessment
Reassessment is not available except when required by referral or deferral.
Original form of assessment 
Form of reassessment 
ILOs reassessed 
Time scale for reassessment 
Whole module 
Written examination (100%) 
113 
August/September assessment period 
Notes: See Physics Assessment Conventions.
KIS Data Summary
Learning activities and teaching methods 
SLT  scheduled learning & teaching activities 
33 hrs 
GIS  guided independent study 
117 hrs 
PLS  placement/study abroad 
0 hrs 
Total 
150 hrs 


Summative assessment 
Coursework 
10% 
Written exams 
90% 
Practical exams 
0% 
Total 
100% 

Miscellaneous
IoP Accreditation Checklist 
 TD01 Zeroth, first and second laws of thermodynamics
 TD02 Temperature scales, work, internal energy and heat capacity
 TD03 Entropy, free energies and the Carnot Cycle
 TD04 Changes of state
 SM02 Statistical basis of entropy
 SM03 MaxwellBoltzmann distribution
 SM04 BoseEinstein and FermiDirac distributions
 SM05 Density of states and partition function

Availability 
unrestricted 
Distance learning 
NO 
Keywords 
Physics; Thermodynamics; Properties; Heat; Energy; System; State; Distribution; Boltzmann; Entropy; Functions. 
Created 
01Oct10 
Revised 
08Aug20 