Transcript Energy - Cloudfront.net

What is energy?
• Energy is the Ability To Do Work
• Energy does things for us.
– It moves cars along the road and boats over
the water.
– It bakes a cake in the oven and keeps ice
frozen in the freezer.
– It plays our favorite songs on the radio and
lights our homes.
– It makes our bodies grow and allows our
minds to think.
– People have learned how to change
energy from one form to another so
that we can do work more easily and
live more comfortably.
– Energy comes in different forms:
• Heat (thermal)
• Light (radiant)
• Mechanical
• Electrical
• Chemical
• Nuclear energy
Ways that energy is converted
into new forms of energy
Energy is in everything
• We use energy to do everything we do, from
making a jump shot to baking our favorite
cookies to sending astronauts into space -energy is there, making sure we have the
power to do it all.
• There are two types of energy -- stored
(potential) energy and working (kinetic)
energy.
– For example, the food you eat contains chemical
energy, and your body stores this energy until
you release it when you work or play.
KINETIC ENERGY
• Kinetic energy is motion––of waves, electrons,
atoms, molecules, substances, and objects.
• Some forms of kinetic energy are:
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Electrical Energy
Radiant Energy
Thermal Energy
Motion Energy
Sound
POTENTIAL ENERGY
• Potential energy is stored energy and the
energy of position––gravitational energy.
• There are several forms of potential energy.
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–
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Chemical Energy
Stored Mechanical Energy
Nuclear Energy
Gravitational Energy
Key Vocabulary
 Energy – the ability to cause changes in matter
 Kinetic Energy – The energy of motion, or
energy in use.
 Potential Energy – The energy an object has
because of its place or its condition.
 Transformation – The transfer of energy back
and forth between kinetic and potential energy.
Types of Energy
Electrical Energy
• Electrical Energy is when
motion, light or heat is
produced by an electrical
current like the electric
coils on your stove.
• Electrical charges moving
through a wire is called
electricity. Lightning is
another example of
electrical energy.
Radiant Energy
(light)
• is energy that travels
in transverse waves.
Radiant energy
includes visible light,
x-rays, gamma rays
and radio waves. Light
is one type of radiant
energy. Solar energy
is an example of
radiant energy.
Heat Energy
• Heat energy is
where motion or a
rise in temperature
is caused by heat
like a fire in your
fireplace
• We use heat for a
lot of things, like
warming our homes
and cooking our
food.
• Heat energy moves
in three ways:
1. Conduction
2. Convection
3. Radiation
Mechanical Energy
Mechanical Energy
is the energy of
motion that does
the work like when
wind turns a
windmill.
Chemical Energy
Chemical Energy is
the chemical
reaction causing
changes; food and
fuel both store
chemical energy.
Sound Energy
Sound Energy is the
movement of energy through
substances in longitudinal
(compression/rarefaction)
waves. Sound is produced
when a force causes an
object or substance to
vibrate––the energy is
transferred through the
substance in a wave.
Gravitational Energy
Gravitational
Energy - where
motion, like water
going over a dam, is
caused by gravity's
pull.
Key Vocabulary
 Solar energy – The energy of sunlight.
 Light energy – The movement of energy that
travels in waves.
 Electrical energy – The movement of energy
through an electrical current.
 Heat energy – The transfer of thermal energy
from one thing to another.
 Mechanical energy – The energy of motion.
 Chemical energy – Energy from a chemical
reaction.
 Sound energy – The movement of energy
through vibrations.
Sources of Energy
Oil and Gas
• Oil and Gas are used
to produce electrical
energy, mechanical
energy, and heat
energy.
• Oil and gas are
pumped from wells
deep in the ground and
under the ocean. They
are then sent through
pipelines to be refined
or cleaned.
Wood and Coal
• Wood and Coal are
used to produce
mechanical, electrical
and heat energy. Coal
is mined underground
near the earth's
surface. It is burned
in its natural form to
produce heat. Coal can
also be converted to a
liquid or gas form.
Water Power (hydropower)
• Water Power can produce
mechanical and electrical
energy. Dams are used to
contain flowing river water
forming lakes and reservoirs. As
water flows downhill it is
channeled to a turbine or water
wheel. The force of the flowing
water turns the turbine or
wheel, which turns a generator
to make the electricity. Water
power has been used for
hundreds of years to create
mechanical energy for grinding,
pumping and running machinery
Sun Power (solar energy)
• Sun Power gives us
heat and light energy.
The sun makes energy
from nuclear fusion.
Billions of times each
second, hydrogen
atoms collide with
each other and
produce helium. Every
second 4.7 million tons
of hydrogen become
energy
Nuclear Power
• Nuclear Power is used
to make electricity.
Inside a reactor atoms
from a fuel called
uranium are split by
neutrons (nuclear
fission). This energy is
released as heat which
changes water into
steam that turns
turbine generators.
Wind Power
• Wind Power is used
for mechanical and
electrical energy.
Wind has been used
for hundreds of
years to help ships
sail and turn
windmills to pump
water for irrigation.
Geothermal Power
• Geothermal is heat energy from deep in the earth using
special pipes buried underground. In some areas of the
world steam is collected and used to turn turbine
generators.
Conservation of energy
The law of conservation
of energy says that
energy is neither
created nor destroyed.
When we use energy, it
doesn’t disappear. We
change it from one form
of energy into another.