1. NS 3310 – Physical Science Studies
Chapter 4 – Heat and Temperature

3. Key Questions
What is heat? What is thermal energy? What is temperature? Is there a difference?
How does heat move around?
Why do some things feel hot and others cold?
How do substances change their state of matter? How is heat involved?
What are the laws of thermodynamics?
What is entropy?

4. Kinetic Energy of Molecules
Solids
Fluids
Liquids
Gases
Plasmas

5. Temperature
Temperature measures the kinetic energy of molecules (this is external energy)
Fahrenheit
Celsius
Kelvin (absolute zero)

6. Thermal Energy Thermal energy is the internal energy of a molecule
Heat is a measure of the internal energy that has been absorbed or transferred from one body to another
Heat is measured in calories (c) or British Thermal Units (BTUs)

7. Specific Heat and Latent Heat
Specific heat changes the temperature of an object
Latent heat changes the phase of the material
For example: Ice to Water to Steam

8. Phase Transitions Latent Heat of Fusion / Melting Latent Heat of
Vaporization /
Condensation
Relative Humidity

9. Heat Flow
Radiation
Conduction
Convection

10. Thermodynamics The First Law of Thermodynamics The Second Law of
Applied Law of Energy Conservation
W = J(QH – QL)
The Second Law of
Thermodynamics
Heat always flows from an area
of higher concentration to an
area of lower concentration
Entropy

11. Perpetual Motion Machine?
Perpetual Motion Machines
Free Energy
Other Scams

12. Why Should We Worry About Pseudoscience?

13. Key Concepts
Thermal energy is the internal and external energy of atoms.
Heat is the transfer of thermal of energy between atoms.
Temperature is a measurement of the kinetic energy of molecules.
Adding heat energy to substances makes their temperature rise (specific heat).
To change the state of a substance requires even more heat (latent heat).
Heat can be transferred by radiation, conduction and convection.
Entropy describes the total energy of a system and tells us that we cannot get more energy out of a system than we put into it.