Transcript energy - Granbury ISD

Energy
Is the ability to do work or
cause change
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Energy is in everything.
There are two types of energy:
Stored (potential) energy
Working (kinetic) energy
• Energy exists in several different forms:
– Mechanical
– Thermal
– Chemical
– Electrical
– Light
– Nuclear.
Energy Law I
The Law of Conservation of
Energy states that energy can not
be created or destroyed; it only
changes form.
Energy Bubble Map
Convection
Mechanical
Conduction
Heat
Nuclear
Radiation
(Thermal)
Energy
The ability to
do work or
cause change
Chemical
Electrical
Light
(Radiant)
Radiant or Light Energy
• Radiant energy is solar and light
energy that travels in electromagnetic
waves.
• Our ultimate energy source is radiant
energy from the sun.
What is Electrical Energy?
o Energy caused by
the movement of
electrons.
o Easily transported
through power lines
and converted into
other forms of energy
o Electrical energy is
the movement
of electrical charges.
What is Mechanical Energy?
o Energy due to a
object’s motion
(kinetic) or position
(potential).
The bowling ball has
mechanical energy.
When the ball strikes
the pins, mechanical
energy is transferred
to the pins!
Examples of Mechanical Energy
What type of energy is shown below?
Thermal Energy
What is Thermal Energy?
Heat energy
o The heat energy of an
object determines how
active its atoms are.
o
A hot object is one whose atoms
and molecules are excited
and show rapid movement.
A cooler object's molecules and
atoms will show less
movement.
What is Chemical Energy?
o Energy that is
available for release
from chemical
reactions.
The chemical bonds in
a matchstick store
energy that is
transformed into
thermal energy when
the match is struck.
What type of energy is shown
below?
Chemical Energy (yummy)
Chemical Energy
Plants can make their own energy
through a process called
photosynthesis. They are the bases for
a food chain. All other living things that
cannot carry on photosynthesis
depend on plants for their energy.
Energy Transformation
• In photosynthesis radiant or light
energy from the sun is changed to
chemical energy in the leaf.
QUIZ TIME!
Electrical energy is transported to
your house through power lines.
When you plug an electric fan to a
power outlet, electrical energy is
transformed (or changed) into
what type of energy? HINT:
Motion
MECHANICAL ENERGY
What type of energy is shown below?
Chemical Energy
Energy is Transformed!
– Chemical potential energy ----Electrical
(kinetic) energy
􀂄 Battery
– Chemical potential energy ------- Motion
(kinetic) energy
􀂄 Food
􀂄
Energy
Transformations
An energy transformation is a change from one form of energy to
another form of energy.
All food has chemical energy.
Consumers eat and their
bodies transform the
chemical energy into thermal
and mechanical (motion)
energy.
chemical
mechanical
The same energy
transformations take
place when we put
gasoline in cars.
The toaster is powered with electricity. The
toaster transforms or changes the
electricity into heat and light.
electrical
The boy is applying a force by pulling
back the slingshot. When he releases it,
whatever he has in the slingshot will fly.
Is the picture an example of
POTENTIAL or KINECTIC energy?
mechanical
thermal
Energy Transformations
Mechanical
Falling water
Blades of the turbine turning
Electrical
Generator
• Next look at the flow map showing the flow
of energy transformations in a car from
starting vehicle to driving. You should see
many types of energy.
Energy Transfer
Sound
(mechanical)
Thermal
Electrical
Mechanical
Chemical
Light
(Electromagnetic)