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
What are the laws of thermodynamics?
What is entropy?
Kinetic Energy of Molecules
Temperature measures the kinetic energy
of molecules (this is external energy)
Kelvin (absolute zero)
Thermal energy is the internal energy of a
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)
Specific Heat and Latent Heat
Specific heat changes the temperature of an
Latent heat changes the phase of the material
For example: Ice to Water to Steam
Latent Heat of Fusion / Melting
Latent Heat of
The First Law of Thermodynamics
Applied Law of Energy Conservation
W = J(Q
The Second Law of
Heat always flows from an area
of higher concentration to an
area of lower concentration
Perpetual Motion Machine?
Perpetual Motion Machines
Why Should We Worry About
Thermal energy is the internal and external energy of
Heat is the transfer of thermal of energy between atoms.
Temperature is a measurement of the kinetic energy of
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
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.