Energy and Energy Resources

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Transcript Energy and Energy Resources

Science Sponge
List and describe the six main types of
simple machines.
List and describe the three types of levers.
Be sure to explain where the load and the
fulcrum would be in each lever.
WELCOME BACK!!!!!
Science Sponge
What is the formula for mechanical
energy?
What is the kinetic energy of a 2,000 kg
bus that is moving at 30 m/s?
What is the gravitational potential energy
of a diver who weighs 600N standing on a
platform that is 8m off the ground?
Science Sponge
List all forms of energy and briefly
describe each.
What is an energy conversion?
Give an example of one energy
conversion that you have encountered
today.
Turn your sponge in
Science Sponge
Please sit with your group and be
prepared to present your energy
conversion along with your visual aid. Your
visual aid should have the type of
conversion written out on it.
Energy and Energy
Resources
Physical Science
Energy and Work: Working
Together
Energy is the ability to do work
There are two main types of energy
kinetic: the energy of motion
Kinetic energy depends on mass and speed.
kinetic energy= mv2
2
M:object’s mass V: object’s speed
Practice
What is the kinetic energy of a car that has
a mass of 2,400 kg and is moving at 20
m/s?
What is the kinetic energy of a 4,000 kg
elephant that is running at 2 m/s? at 4
m/s? How do the two kinetic energies
compare with one another?
Energy and Work: Working
Together
Potential energy is the energy an object
has based on its position.
Gravitational potential energy is energy
transferred to an object based on the object
being lifted and put into a different position.
gravitational potential energy= weight x height
Gravitational potential energy is equal to the
amount of work done on an object to lift it to a
certain height.
Practice
What is the gravitational potential energy
of a cat that weighs 40 N standing on a
table that is 0.8 m above the ground?
What is the gravitational potential energy
of a driver who weighs 500 N standing on
a platform that is 10 m off the ground.?
Forms of Energy
 Mechanical
 Thermal
 Chemical
Energy can be
transferred, or
converted, from
one form to
another!
 Electrical
 Electromagnetic
 Nuclear
 Sound
Chemical Energy
Energy stored in chemical bonds of
molecules. It depends on the position
and arrangement of the atoms in a
compound.
Food
Battery
Nuclear Energy
Energy stored in the nucleus of an
atom from fission or fusion
Sun
Stars
Nuclear Power
Plant
Mechanical Energy
Energy associated with the total motion of
an object.
Mechanical Energy = PE + KE
chewing
frog dancing
riding a bike
moving fan blades
Thermal Energy
 Total energy of the moving particles in a
material.
 Thermal energy is produced any time energy
changes form
All objects give off
thermal energy
Ice cream melting
gains thermal
energy
Electrical Energy
Moving electrons that produce
electricity.
Static Shock
Lightening
Computers/TVs/
Radios
Lights
Electromagnetic Energy
Energy that travels in
electromagnetic waves
Visible light
UV Rays
Microwaves
Sound Energy
Energy is created because of
vibrating particles.
Travels in mechanical waves
Musical
instruments
Vocal cords
Energy Conversions
An energy
conversion is
change from one
form of energy to
another.
Energy Conversion
Create a scenario where you may
experience energy conversions.
One person in your group is responsible
for creating a visual that represents your
conversion.
You have fifteen minutes to complete this
activity and be prepared to share with the
rest of the class.
Energy Conversions
Elastic Potential Energy
Have you ever been popped by a rubber
band???
How is elastic potential energy stored and
released?
What Did You Eat for Breakfast?
Chemical energy comes from the food you
eat. Your body uses chemical energy to
function.
What’s your favorite breakfast food?
Energy Conversions in Plants
Chemical energy in the food you eat
comes from the Sun’s energy. Light
energy is changed into chemical energy
through photosynthesis.
It’s an endless process and energy is
always going somewhere!!
Can you imagine your life without energy
conversions?
Energy is Conserved Within a
Closed System
A closed system is selfish, it only transfers
energy amongst itself.
Volunteers???
In your own words, describe a closed
system.
Energy is Conserved Within a
Closed System
A closed system is a group of objects that
transfer energy only to each other.
Law of Conservation of Energy
Energy cannot be created or destroyed. The
total amount of energy in a closed system is
always the same.
Think about all of the energy conversions
involved in having a light on.
No Conversion Without Thermal
Energy
Any time one form of energy is converted
into another form, some of the original
energy always gets converted into thermal
energy.
Go back the light bulb…
Energy Resources
Do you remember renewable, and nonrenewable resources from sixth grade?
These are a result of fossil fuels
There are three types: coal, petroleum
(crude oil), gasoline