PHY1002 Thermal Physics

2007-2008

Code: PHY1002
Title: Thermal Physics
Instructors: Dr P.G. Petrov
CATS credits: 10
ECTS credits: 5
Availability: unrestricted
Level: 1
Pre-requisites: N/A
Co-requisites: N/A
Background Assumed: AS level Physics or equivalent
Duration: Semester II
Directed Study Time: 22 lectures
Private Study Time: 66 hours
Assessment Tasks Time: 12 hours
Observation report: awaiting notification

Aims

Thermodynamics is one of the most fundamental topics in physics, in chemistry, and in engineering. Its applications can be found, for example, in the determination of the structure of stars, in the understanding of biochemical processes and in the design of everyday goods like refrigerators and cars. The aim of this module is to develop a sound understanding of the central concepts of thermodynamics, such as thermodynamic equilibrium, temperature and heat. A first-principles approach is adopted, as most students have not studied thermal physics previously, with emphasis on basic understanding rather than on the development of mathematical theory. The module is designed to be a precursor to the core Statistical Physics module (PHY2201) taken by second-year students.

Intended Learning Outcomes

Students will be able to:

• describe the concept of temperature and explain how it is measured,
• give examples of heat transfer processes,
• state the zeroth and first laws of thermodynamics and carry out applications of the first law to various thermodynamic processes,
• describe the molecular model of a gas,
• explain equipartition of energy and distinguish between properties of systems (state variables such as volume or energy) and properties of processes (such as heat or work).

Transferable Skills

Students are asked to read through and understand the previous lecture by the time the next lecture is given. Students have therefore to develop a work strategy and ethos to achieve this. They are encouraged to read around the subject and discuss it with their peers, their tutor and the lecturer. They learn to recognise potential learning resources and gain the ability to work with other people.

Learning and Teaching Methods

Lectures, directed reading, tutorials and problems classes, e-learning resources. Students are also given short problems to illustrate various topics as they are being covered during the lectures and the lecturer goes through these with the class.

Assignments

Homework sheets are given and the solutions are discussed in problems classes and in tutorials.

Assessment

Two 30-minute mid-semester tests (40%), problems classes (10%) and one 90-minute examination (50%).

Syllabus Plan and Content

Note: references to sections in the recommended text are given in square brackets.

1. Basic Ideas
   Systems and surroundings; Microstates; State variables [16.2]; The mole [16.3].
2. Thermodynamic Equilibrium
   Definition of a thermodynamic state; Thermodynamic equilibrium [15.2]; Adiabatic and diathermal walls; Thermal contact The zeroth Law [15.2]; Thermal equilibrium and temperature [15.3].
3. Temperature and Related Topics
   Thermometric systems and properties [15.3]; Constant-volume gas thermometer [15.4]; Triple point of water [15.4]; The ideal-gas temperature; Temperature scales [15.3]; Equations of state [16.2]; p/V isotherms [16.2]; Van der Waals equation of state; Thermal expansion [15.5]; Quantity of heat [15.6]; Heat Capacity and latent heat; Phase changes [15.7]; Mechanisms of heat transfer: Conduction, convection and radiation [15.8].
4. Processes
   Processes taking a system between equilibrium states [17.6]; Reversible and irreversible processes [18.2]; Processes with energy transfer; Energy transfer in the form of nondissipative work [17.2, 17.3]; Energy transfer in the form of dissipative work [17.2, 17.3]; Energy transfer in the form of heat (nonisothermal or isothermal).
5. Internal Energy, Heat and the First Law of Thermodynamics
   Joule's experiments; Adiabatic work; Internal energy as a state variable [16.2]; Definition of heat (the first law of thermodynamics) [17.5]; Form of the first law for infinitesimal changes; Heat and work in general compression/expansion processes [17.6];
6. The Ideal Monatomic Gas
   Pressure; Microscopic interpretation of temperature; Internal energy of an ideal gas; Equipartition of energy; Polyatomic gases; Distribution functions; The one-component Maxwell velocity distribution [16.4]; The Maxwell speed distribution; The mean speed, mean square speed and "most probable" speed; The mean free path and thermal conductivity; Equipartition of energy [16.5].
7. Applications of First Law to Ideal Gases
   Free expansion; Heat capacities of ideal gases [17.8]; General equation of compression/expansion adiabats [17.9].
8. Entropy and the Second Law
   The Carnot cycle; Heat engines and heat pumps; Entropy as a function of state; The Fundamental Thermodynamic Relationship.

Core Text

Young H.D. and Freedman R.A. (2000), University Physics (with Modern Physics) (10^th edition), Addison-Wesley, ISBN 0-201-60336-5 (UL: 530 YOU)

Supplementary Text(s)

Not applicable

Formative Mechanisms

This module is supported by problems classes and tutorials. Students are able to monitor their own progress by attempting to answer questions put by the lecturer as part of the lecture. The graded mid-semester test scripts are discussed by tutors. Students with specific problems should first approach their tutor, and if the problem is not resolved, the lecturer.

Evaluation Mechanisms

The module will be evaluated using information gathered via the student representation mechanisms, the staff peer appraisal scheme, and measures of student attainment based on summative assessment.