Transcript Energy notes

Warm-up
Energy Reading
Lesson Essential Question
What are the different types of
energy? How is energy transferred
or transformed?
Energy CANNOT be
created or destroyed…
The law of conservation of energy
states that energy may neither be
created nor destroyed.
Therefore the sum of all the energies
in the system is a constant.
PE + KE = 0
Energy Classification
There are two main forms of energy, kinetic
energy (motion) and potential energy
(position).
To further classify energy, these forms are
sometimes further described as thermal
(heat), elastic, electromagnetic (light,
electrical, magnetic), gravitational, chemical
(food), and nuclear energy.
Energy can be transferred and
transformed
Energy Transfer:
Energy can be transferred from one
location to another
The two ways that energy can be
transferred are by doing work and
heat transfer.
When work is done on an object, it
results in a change in the object's
motion
Energy is often defined as the
ability to do work.
Energy can be transferred and
transformed
Heat is given off when an object's thermal
energy is transferred. Thermal energy can be
transferred in three ways: by conduction, by
convection, and by radiation.
Conduction
Conduction is the transfer of
energy from one molecule to
another.
Convection
Convection is the movement of
heat by a liquid such as water or
a gas such as air.
Radiation
is the transfer of heat by electromagnetic
waves. When infrared rays strike a material,
the molecules in that material move faster.
Energy Transformation
Energy in a system may be
transformed so that it resides in a
different state. Energy in many
states may be used to do many
varieties of physical work.
Energy may be used in natural
processes or machines, or else to
provide some service to society
(such as heat, light, or motion).
Examples…
An internal combustion engine converts the
potential chemical energy in gasoline and
oxygen into heat, which is then transformed
into the propulsive energy (kinetic energy
that moves a vehicle.)
Example
A solar cell converts solar radiation into
electrical energy that can then be used to
light a bulb or power a computer.
Example of energy
transformation
Type of Energy
Kinetic
Gravitational
Elastic
Electric
Magnetic
Mechanical
Heat
Nuclear
Light
Chemical
Description and Examples