Lesson Objectives – the students should be able to:
- Explain what is meant by a physical system and distinguish between an open system and a closed system.
- State the first law of thermodynamics and use this law to solve problems.
- Distinguish between an isothermal process, isobaric process, isochoric process and adiabatic process and draw a PV diagram for each process.
- Calculate the work done by a gas from a PV diagram. Use the equations for an ideal gas and for the internal energy of a gas to calculate the change in internal energy of a gas and the heat added or removed during a thermodynamic process.
- Calculate the amount of heat which must be added or removed to change the temperature of a gas held in a closed container under conditions of constant volume or constant pressure.
- Write from memory and explain the meaning of three equivalent ways of stating the second law of thermodynamics.
- Use the first and second laws of thermodynamics to solve problems involving a Carnot engine.
- Distinguish between a reversible process and an irreversible process. Give examples of each type of process.
- Determine the change in entropy for a system in which the thermodynamic process is either reversible or irreversible.
- Distinguish between macrostate and microstate and solve problems involving the statistical interpretation of entropy.
Lecture on The Laws of Thermodynamics PPT
Back to Homepage
Summary of Chapter 15
- First law of thermodynamics:
- Isothermal process: temperature is constant.
- Adiabatic process: no heat is exchanged.
- Work done by gas at constant pressure:
- Heat engine changes heat into useful work; needs temperature difference.
- Efficiency of a heat engine:
- Upper limit on efficiency:
- Refrigerators and air conditioners do work to extract heat from a cooler region and send it to a warmer region:
- A heat pump is similar:
- Second law of thermodynamics:
- heat flows spontaneously from a hot object to a cold one, but not the reverse
- a given amount of heat cannot be changed entirely to work
- natural processes tend to increase entropy.
- Change in entropy:
- Entropy is a measure of disorder.
- As time goes on, less and less energy is available to do useful work.
Units of Chapter 15 – Keywords
- The First Law of Thermodynamics
- Thermodynamic Processes and the First Law
- Human Metabolism and the First Law
- The Second Law of Thermodynamics – Introduction
- Heat Engines
- Refrigerators, Air Conditioners, and Heat Pumps
- Entropy and the Second Law of Thermodynamics
- Order to Disorder
- Unavailability of Energy; Heat Death
- Evolution and Growth; “Time’s Arrow”
- Statistical Interpretation of Entropy and the Second Law
- Thermal Pollution and Global Warming
Download Lecture Handout
credit: Giancoli Physics©2013 www.PinoyBIX.org