PHY2023 Thermal Physics 2013-14
Dr M.E. Portnoi
Delivery Weeks: T2:01-11
Level: 5 (NQF)
Credits: 15 NICATS / 7.5 ECTS
Enrolment: 71 students (approx)


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. Real-world examples of the key ideas are presented and their application in later modules such as PHY2024 Condensed Matter I and PHY30703 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 steam-engines, 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 N-body system containing 1023 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:

Syllabus Plan

  1. Introduction
    Brief historical survey.
  2. Classical Thermodynamics
    1. Zeroth, first and second laws of thermodynamics
    2. Temperature scales, work, internal energy and heat capacity
    3. Entropy, free energies and the Carnot Cycle
    4. Changes of state
    5. Heat engines and heat pumps
    6. The Fundamental Thermodynamic Relationship
    7. Thermodynamic potentials and Maxwell relations
    8. Real gases
  3. Statistical Physics
    1. Maxwell-Boltzmann distribution
    2. Boltzmann energy sharing
    3. Microscopic / statistical interpretation of entropy
  4. Statistical Thermodynamics
    1. Density of states
    2. The partition function Z
    3. Macroscopic functions of state in terms of Z.
    4. Equation of state for an ideal monatomic gas
    5. The equipartition theorem
    6. Quantum statistical mechanics; the Bose-Einstein and Fermi-Dirac distributions

Learning and Teaching

Learning Activities and Teaching Methods

Description Study time KIS type
22×1-hour lectures 22 hours SLT
5×6-hour self-study packages 30 hours GIS
8×2-hour problems sets 16 hours GIS
Problems class support 8 hours SLT
Tutorial support 3 hours SLT
Reading, private study and revision 71 hours GIS


Weight Form Size When ILOS assessed Feedback
0% Exercises set by tutor 3×1-hour sets (typical) Scheduled by tutor 1-14 Discussion in tutorials
0% Guided self-study 5×6-hour packages Fortnightly 1-14 Discussion in tutorials
10% 8 × Problems sets 2 hours per set Weekly 1-14 Marked in problems class, then discussed in tutorials
15% Mid-term Test 30 minutes Weeks T2:06 1-13 Marked, then discussed in tutorials
75% Examination 120 minutes May/June assessment period 1-13 Mark via MyExeter, collective feedback via ELE and solutions.


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:


Further Information

Prior Knowledge Requirements

Pre-requisite Modules Properties of Matter (PHY1024) and Mathematics for Physicists (PHY1026)
Co-requisite Modules Mathematics with Physical Applications (PHY2025)


Re-assessment is not available except when required by referral or deferral.

Original form of assessment Form of re-assessment ILOs re-assessed Time scale for re-assessment
Whole module Written examination (100%) 1-13 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%


IoP Accreditation Checklist
  • TD-01 Zeroth, first and second laws of thermodynamics
  • TD-02 Temperature scales, work, internal energy and heat capacity
  • TD-03 Entropy, free energies and the Carnot Cycle
  • TD-04 Changes of state
  • SM-02 Statistical basis of entropy
  • SM-03 Maxwell-Boltzmann distribution
  • SM-04 Bose-Einstein and Fermi-Dirac distributions
  • SM-05 Density of states and partition function
Availability unrestricted
Distance learning NO
Keywords Physics; Thermodynamic; Properties; Heat; Energy; System; State; Distribution; Boltzmann; Entropy; Functions.
Created 01-Oct-10
Revised 01-Oct-11