Energy
Energy is never created or
destroyed. It is always stored
or transferred.
What is energy?
Energy is the ability to do work or cause
change.
States of energy
All forms of energy can be in either
one of two states:
 Potential
 Kinetic

Potential Energy


Potential Energy is stored energy.
i.e. stored chemically in fuel and in foods.
Kinetic Energy

The energy of motion.

Potential Energy is converted to Kinetic
Energy. When the object begins to move,
the object now converts the stored energy
(potential energy) into kinetic energy.
Kinetic Energy

The faster the motion, the greater the
kinetic energy. When the roller coaster
starts down the hill, it has kinetic energy.
The point where the car is going the
fastest, is where the kinetic energy is the
greatest.
Forms of Energy


Energy can be converted from one form to
another form.
Forms include:
Chemical
 Heat= thermal energy.
 Electrical
 Sound
 Mechanical= energy of movement.

Chemical Energy


Stored in chemical bonds holding the
atoms of compounds together.
Examples: food, wood, batteries, fossil
fuels
Chemical Energy
Plants can make their own energy through
a process called photosynthesis. All
other living things can get energy from
eating plants or eating animals that eat
plants.
Chemical Energy

The energy we eat is stored as potential
chemical energy until we need it. When
we use the energy through an activity it
becomes kinetic mechanical energy.
Chemical Energy
Electrical Energy


Energy of moving electrons. It is invisible but it
is the most useful form.
Electrical energy can come from many different
sources.
Energy Transformation
Mechanical Energy

When we move or work we are using
mechanical energy.
Heat and Light Energy





Heat and light are both forms of energy.
We can see light energy.
We feel heat energy.
Some light energy comes from the sun.
When sunlight strikes the earth, it
changes to heat.
Energy Conversions