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Energy of Objects in Motion
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Energy of Objects in Motion
Click on the topic to go to that section
· Energy and its Forms
· Mechanical Energy
· Energy of Motion
· Stored Energy
· Conservation of Energy
· Types of Energy Resources
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Review from Last Unit
Why does a force cause an object to accelerate?
Answer
In the previous units we have been studying the motion of objects.
We talked about how far and fast an object goes if a force is applied to it.
Slide 5 / 111
Energy and its Forms
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of Contents
Slide 6 / 111
What is Energy?
Energy is a measurement of an object's ability to do work.
How would you
define work?
How would you
know if any work
was being done?
Slide 7 / 111
What is Energy?
Energy is a measurement of an object's ability to do work.
Work is defined as applying a force in order to move an object in a
given direction. The more work that is done by an object, the more
energy it exerts.
Since energy is equal to work, the unit for both is the same, the
Joule (J).
1 Joule = 1 Newton-meter
Slide 8 / 111
Work
Work can only be done to a system by an external force; a
force from something that is not a part of the system.
So let's say our system is
a plane and the gate
assistance vehicle.
When the vehicle comes
along and pushes back
the plane, it increases
the energy of the plane.
The assistance truck is
essentially doing work on
the plane.
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Work
The amount of work done is the change in the amount of energy
that the system will experience. This is given by the equation:
W = E final - Einitial
· When a force is applied which causes the object to speed up and
move a distance, the work is _______________.
· If a resistive force was applied which caused the object to slow down
over a distance, or not move at all, the work would be ____________.
(think about acceleration)
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Positive Work
If the object moves in the
same direction as the
direction of the force,
the energy of the system
is increased.
The work is positive:
W > 0.
They can push the truck to get it to move!
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Negative Work
If the object moves in the direction
opposite the direction of the force
then the work is negative: W < 0.
The energy of the system is
reduced.
Pushing on the wall as hard as
they can won't ever move the wall!
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Mechanical vs. Non-Mechanical Energy
Energy exists in many forms, but can be broken down into two major forms:
Mechanical Energy - The Energy of an object due to its motion and
position. Mechanical Energy is the sum of the Kinetic and Potential
Energy of an object. Mechanical Energy is usually used to describe a
large object.
Non-Mechanical Energy - The Energy of an object that is not due to
it's motion or position. Non-Mechanical Energy usually describes an
object at it's atomic level.
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1 Which of the following is the unit for energy?
B Newton
C Second
D Joule
Answer
A Meter
Slide 14 / 111
A positive
B negative
Answer
2 A wagon is rolling down a hill, a man tries to stop the
wagon by trying to push it back up the hill but he is
unsuccessful. Is the man doing positive or negative
work?
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3 A boy kicks a soccer ball into a net. Did the boy do
positive or negative work on the ball?
B negative
Answer
A positive
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A positive
B negative
Answer
4 A woman walks across an icy sidewalk that has been
covered in salt to help make it less slippery. Is the
salt doing positive or negative work on the woman's
shoes?
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Mechanical Energy
Return to Table
of Contents
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Forms of Mechanical Energy
Mechanical Energy can be broken down into two different types of Energy:
Energy of Motion, which is called Kinetic Energy and Stored Energy, which is
called Potential Energy. Potential Energy has two forms, Gravitational and
Elastic, depending upon how the Energy is stored.
__________ Energy
__________ Energy
Write the underlined
words into the
correct place in the
diagram.
__________ Energy
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5 Which of the following is a form of Mechanical
Energy?
B Thermal
C Chemical
D Solar
Answer
A Kinetic
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Energy of Motion
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of Contents
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6 Which of the following is a type of energy which is
used to describe the motion of an object?
B Nuclear Energy
C Potential Energy
D All of the above
Answer
A Electrical Energy
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Energy of Motion
In order for an object to move, one of two scenarios has to occur:
The object uses some of the potential energy that it had stored.
The object is being given energy from an outside source.
In either case, now that the object is in motion, the object is
experiencing Kinetic Energy.
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Kinetic Energy
An object's state of motion can be described by looking at the
amount of kinetic energy that the object has at that moment in time.
Since the state of motion
of an object can change
with time, the kinetic
energy of an object can
also change with time.
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Kinetic Energy
The amount of Kinetic Energy that an object possesses is
dependent on two factors: mass and velocity.
Both of these factors are directly proportional to the kinetic
energy. We talked about this mathematical relationship in the
last chapter. What did directly proportional mean?
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Kinetic Energy, Mass, Velocity
The larger the mass, the more energy is needed to move the object,
therefore the _______________ the kinetic energy.
Since kinetic energy is the energy of motion,
the object has to have a velocity to have kinetic energy. The larger the
velocity, the __________________ the kinetic energy.
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How Does Kinetic Energy Depend on Mass?
If two identical objects are moving at the same velocity then they will have
the same kinetic energy.
If however, one object has more mass
than the other while traveling at the
same velocity, the heavier object will
have more kinetic energy.
v = 5 m/s
v = 5 m/s
A tennis ball and a bowling ball are both shown above. The bowling ball is
heavier than the tennis ball. If they were both to move at the same velocity,
which ball would have more kinetic energy?
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Velocity vs. Speed
Remember that velocity is another way to measure motion. Simply put,
velocity is the speed of an object with direction. Speed does not have a
direction, so we call speed a scalar quantity.
Since velocity has both magnitude and direction, it is a vector quantity.
Runner's speed: 10 km/hr
Runner's velocity: 10 km/hr to the East
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What is Kinetic Energy?
In this picture, the hare is moving faster
than the tortoise at this point.
If we assumed that they had the same mass, who would have
more kinetic energy? Why? Discuss this with a partner.
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How Does Kinetic Energy Depend upon
Velocity?
If two identical objects are moving at the same velocity then they will have
the same kinetic energy. If however, one of the object's is moving faster,
the one which is moving faster will have more kinetic energy.
v = 5 m/s
v = 10 m/s
In the diagram above, two identical tennis balls are moving. Which tennis
ball has more kinetic energy and why?
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A a police car
B an ambulance
C a Firetruck
D they all have the same kinetic energy
Answer
7 Three different emergency vehicles are noticed
driving on the highway at a speed of 25 m/s. Which
of the following cars have the most kinetic energy at
that moment?
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A a little league pitcher
B a high school pitcher
C a major league pitcher
D they all had the same kinetic energy
Answer
8 Three different baseball pitchers had the speed of
their fastball measured by a radar gun. Which of the
following pitcher's fastball had the smallest amount
of kinetic energy?
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9 Which of the following situations has the lowest
kinetic energy? Be ready to explain your answer.
B a child riding a bike
C a woman driving a car
D it is impossible to tell
Answer
A a man sitting on a park bench
Slide 33 / 111
Calculating Kinetic Energy
Kinetic Energy can be solved for by using the equation:
KE =
1
2
mv2
Fill in the table below.
Name
variable
units
Kinetic Energy
m
m/s
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Example - Calculating Kinetic Energy
1
KE = 2 mv2
KE = (0.5)(1000 kg)(5 m/s)2
KE = (0.5)(1000 kg)(25 m2/s2)
KE = 125,000 J
Teacher Notes
A car, which has a mass of 1,000 kg, is moving with a velocity of 5 m/s.
How much Kinetic Energy does the car possess?
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Answer
10 A 10 kg snowball is rolling down a hill. Just before
reaching the bottom, it's velocity is measured to be
10 m/s. What is the Kinetic Energy of the ball at this
position?
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Answer
11 A 100 kg man running back in football is running with
a velocity of 2 m/s. What is his Kinetic Energy?
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Answer
12 A 2000 kg car with a velocity of 20 m/s slows down
and stops at a red light. What is the change in
Kinetic Energy?
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Answer
13 A 50kg girl rode her 12 kg bicycle in a race. She started
from rest and peddled with a velocity of 10 m/s. What
is the change in Kinetic Energy of the girl and her
bicycle?
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Thinking Mathematically
KE =
1
mv2
2
We have already said that mass and velocity are directly proportional to
kinetic energy. This means that if the mass of the object doubles, the
kinetic energy ___________. If the mass of the object increases by a
factor of 5, then the kinetic energy___________ by ______________.
If the mass of the object decreases by half, then the kinetic
energy will ____________ by ___________.
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Thinking Mathematically
Kinetic Energy can be solved by using the equation:
KE = 1 mv2
2
Looking at this equation again, we can see that the kinetic
energy is also directly proportional to the square of the velocity.
This means that if the velocity doubles, the kinetic energy
increases by a factor of 4. 22=4
If the velocity is quadrupled, then the kinetic energy increases
by a factor of 16. 42= 16
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Answer
14 If the mass of a wagon is doubled, by what factor
does the KE increase?
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Answer
15 If the velocity of a wagon is tripled, by what factor
does the KE increase?
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Answer
16 Two balls are moving with the same velocity, ball A
has a mass of 10kg and ball B has a mass of 40kg.
How much more KE does ball B have?
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Stored Energy
Return to Table
of Contents
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Where does Kinetic Energy Come From?
Imagine a roller coaster car that is at the top of the first hill and is
stopped.
Does the car stay
stopped at the top
of the hill for the
entire ride?
What happens?
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Where does Kinetic Energy Come From?
Once the car leans over the
edge, gravity pulls it down.
The ride is taking advantage
of the gravitational attraction
between the car and Earth to
give the car kinetic energy
and make it go faster as it
falls.
The kinetic energy the car is
receiving is coming from
another type of energy called
Potential Energy.
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Where does Kinetic Energy Come From?
Potential Energy is energy that an object has stored within it due to
it's position, in this case, the car's height.
There are two forms of Potential Energy that we will be looking at in
this unit:
Gravitational Potential Energy
and
Elastic Potential Energy
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Gravitational Potential Energy
An object has a certain amount of
energy naturally associated with it.
If the object has a force acting on it
from a distance (like gravity) and there
is no object supporting the object, then
the amount of energy that the object
has is called the Gravitational
Potential Energy.
This energy is stored energy and
means that it can be used at a later
time to cause an object to move.
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Gravitational Potential Energy
Gravitational Potential Energy is determined by three factors: mass,
gravity, and height. All three factors are directly proportional to
energy.
Mass: The heavier the object is, the _______
gravitational potential energy the object has.
Gravity: The larger the gravity, the _________ gravitational
potential energy the object has. Since gravity on Earth is
considered a constant, this will not change.
Height: The higher the object is off the ground, the _________
gravitational potential energy the object has.
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How Does Mass Affect Gravitational
Potential Energy
In this picture, the mass of a tennis ball was doubled when it was at
the same height off of the ground.
m = 2 kg
h=2m
m = 1 kg
h=2m
How does the gravitational
potential energy compare
for the two objects?
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How Does Mass Affect Gravitational
Potential Energy
m = 2 kg
m = 1 kg
mass: double = doubled
gravity: stayed the same = no change
h=2m
h=2m
height: stayed the same = no change
Since the only thing that changed was the mass, which doubled,
the gravitational potential energy also doubled.
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How Does Height Affect Gravitational
Potential Energy
In this picture, the same object, a tennis ball, is lifted to a height
that is twice as high.
How would the Gravitational
Potential Energy compare at the
higher height?
h=4m
h=2m
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How Does Height Affect Gravitational
Potential Energy
mass: stayed the same = no change
gravity: stayed the same = no change
height: doubled = doubled
h=4m
h=2m
Since the only thing that changed was the height which doubled,
the gravitational potential energy also doubled.
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A they are the same
B twice as large
C ten times as large
D thirty times as large
Answer
17 A bowling ball which has a mass that is 30 times
larger than a softball, is lifted to the same height as
the softball. How much larger is the Gravitational
Potential Energy for the bowling ball compared to the
softball?
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18 Two balloons are floating in the sky. If one balloon is
floating at a height of 30 m and the other, identical
balloon, is floating at a height of 45 m, how much
larger is the Gravitational Potential Energy of the
higher balloon compared to the lower one?
B they are the same
C 1.5 times larger
D twice as large
Answer
A half as large
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Calculating Gravitational Potential Energy
Gravitational Potential Energy can be solved by using the equation:
GPE = mgh
Name
Gravitational
Potential Energy
Gravity
variable
m
units
m
Slide 57 / 111
Example - Calculating Gravitational
Potential Energy
A basketball, whose mass is 0.5 kg, is held at a height of 2 m above
the ground. How much Gravitational Potential Energy does the
basketball possess?
GPE = mgh
GPE = (0.5 kg)(9.8 m/s2)(2 m)
GPE = 9.8 J
Slide 58 / 111
Answer
19 A 50 kg diver is standing on top of the 10 m platform.
How much Gravitational Potential Energy does he
have?
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Answer
20 A 3,000 kg hot air balloon is hovering at a height of
100 m above Earth's surface. How much
Gravitational Potential Energy does it possess?
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Thinking Mathematically
GPE = mgh
GPE = mgh
We know that GPE is directly proportional to mass, to gravity, and to
height. This means that as any of these increase, the GPE increases
by the same factor. If any of these decrease, then the GPE decreases
by the same factor.
Slide 61 / 111
Answer
21 A ball is dropped from 30m, it is then dropped from
60m. By what factor does the GPE increase?
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22 A 3kg object and a 9kg object are both dropped from
the same height. Which has more GPE?
Answer
A 3kg object
B 9kg object
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Answer
23 A 3kg object and a 9kg object are dropped from the
same height. How much less is the GPE of the 3kg
object than the 9kg object?
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Elastic Potential Energy
Sometimes it is not possible to take advantage of gravity's pull on
an object to change it's Kinetic Energy, such as if the object is on a
flat surface.
One type of Potential Energy is
called Elastic Potential Energy.
Looking at the picture to the right,
can you come up with an idea about
what Elastic Potential Energy is?
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Elastic Potential Energy
Elastic Potential Energy is determined by two factors: the elasticity
of the material and how far it is stretched or compressed.
Think about what you know
about rubber bands.
Do you think elasticity and
distance stretched are directly
proportional or indirectly
proportional to the energy?
Talk about this at your table.
Slide 66 / 111
Elastic Potential Energy
Elasticity: The more elastic that a material is, the more elastic
potential energy the object has.
Distance of stretch (or compression): The
larger the distance of the elastic material is
stretched (or compressed) the more elastic
potential energy it has.
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What is the Difference Between Stretching
and Compression in a Spring
Think about a slinky sitting on
a desk. A spring has no
potential energy stored in it if it
is neither stretched nor
compressed. This distance, as
shown in figure (a) is called the
relaxed length.
Stretching a spring is caused
when the spring is pulled
increasing the length of the
spring compared to the relaxed
length, as shown in figure (b).
(a)
(b)
(c)
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What is the Difference Between Stretching
and Compression in a Spring
Compressing a spring is caused when the spring is squeezed which causes
a decrease in the length of the spring compared to the relaxed length, as
shown in figure (c).
In this diagram, both figures (b) and (c) would have the same elastic
potential energy because both springs are displaced the same distance, x.
(a)
(b)
(c)
Slide 69 / 111
How Does Elastic Potential Energy Depend
Upon Compression
In the diagram to the right, both pictures show
a spring, which is an elastic material.
In the top picture however, the spring is not
stretched or compressed, and therefore there
is no potential energy stored in the spring.
In the bottom picture, the spring is compressed
and therefore elastic potential energy is stored
in the spring.
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A When she is standing on the trampoline
B When she is in the air
C When she lands on the trampoline after jumping
D she will always have the same elastic potential
energy
Answer
24 A child jumps on a trampoline in his backyard. At
which of the following will she have more elastic
potential energy?
Slide 71 / 111
Calculating Elastic Potential Energy
Elastic Potential Energy can be solved by using the equation:
EPE = 1 kx2
2
EPE = Elastic Potential Energy (J)
k = spring constant (N/m)
x = distance of stretch or compression (m)
Slide 72 / 111
Spring Constant
1 2
EPE = kx
2
The energy and distance variables in this equation are likely familiar.
But what is the spring
constant (k)? Look at the two
springs to the right. Which
would be easier to stretch?
Every spring has a different
degree of stretchiness and
that is what the spring
constant represents.
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Spring Constant
1 2
EPE = kx
2
Breaking down the units for
spring constant also explains
what the variable represents.
Can you explain what
Newtons per Meter (N/m)
means?
Slide 74 / 111
Example - Calculating Elastic Potential
Energy
EPE = 12 kx2
EPE = ( 12 )(10 N/m)(1 m)2
EPE = ( 1 )(10 N/m)(1 m2)
2
EPE = (5 N*m)
EPE = 5 J
Teacher Notes
A spring, which has a spring constant of 10 N/m, is stretched a
distance of 1 m. How much Elastic Potential Energy is stored in the
spring?
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Answer
25 A child bouncing on a pogo stick compresses the
spring by 0.25 m. If the spring constant of the spring
on the bottom of the pogo stick is 200 N/m, what is
the Elastic Potential Energy stored in the spring
when it is compressed?
Slide 76 / 111
Answer
26 A rubber band with a spring constant of 40 N/m is
pulled back 0.5 m. How much Elastic Potential
Energy is stored in the elastic band?
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27 Which of the following would you expect to have the
smallest spring constant?
B a slinky
C a spring in a pen
D a trampoline spring
Answer
A a garage door spring
Slide 78 / 111
Thinking Mathematically
EPE =
1 2
kx
2
1
KE = 2 mv2
Notice that the equation for EPE is similar to the equation for KE.
Remember that in the equation for KE, energy was directly
proportional to the mass and it was also directly proportional to
the square of the velocity.
What do you think the relationship is between EPE and the
spring constant?
What do you think is the relationship between EPE and the
distance the spring is stretched or compressed?
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Thinking Mathematically
EPE =
1 2
kx
2
EPE is _________________________ to the spring constant.
EPE is _________________________ to the square of the
distance the spring is compressed or stretched.
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Answer
28 If the spring constant is tripled, by what factor does
the EPE increase?
Slide 81 / 111
Answer
29 If the spring constant is halved, by what factor does
the EPE decrease?
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Answer
30 If the distance a spring is stretched is increased by a
factor of 6, by what factor is the EPE increased?
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Conservation of Energy
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of Contents
Slide 84 / 111
Conservation of Energy
What we have looked at so far is that an object has Kinetic Energy if
the object is in motion. The faster that the object is going, the more
Kinetic Energy it has.
In order for an object's Kinetic Energy to increase, it must get more
energy from somewhere. But where would it get that energy?
Hint: think back to the roller
coaster. What kind of
energy did it have at the
top of the hill?
Slide 85 / 111
Conservation of Energy
In order for an object's Kinetic Energy to increase, it must take
Energy from it's stored energy, which we call Potential Energy.
When this happens, the Potential Energy that an object
possesses decreases.
When this happens, the Total Energy (TE) in that closed system
contains does not change. This is called the Conservation of
Energy.
TEi = TEf
i = initial
f= final
Slide 86 / 111
Conservation of Energy
If the amount of energy that we start with "Ei" and the amount we
end up with as "Ef" then we would say that if no energy is added to
or taken away from a system.
TEi = TEf
When looking at the Mechanical Energy, the total energy possible
is the Potential Energy (PE) and the Kinetic Energy (KE) added
together.
(PE + KE)i = (PE + KE)f
Slide 87 / 111
Conservation of Energy
(PE + KE)i = (PE + KE)f
If any object at any height is being supported, then the
Gravitational Potential Energy is 0 J.
If a spring is not stretched or compressed, then the
Elastic Potential Energy is 0 J.
If the object is not moving at any position, then the
Kinetic Energy is 0 J.
Slide 88 / 111
What is Meant by a Closed System?
A closed system involves only the material that is being measured.
Everything else is called the surroundings.
In the diagram of the ball falling
shown to the right, the ball and Earth
make up the system as the
Gravitational Potential Energy that is
stored in the ball due to it's height
from Earth's surface is transferred to
Kinetic Energy as the ball falls.
Slide 89 / 111
What If Both Types of Mechanical Energy
Are Present at the Same Location?
In the case when an object is moving at some height above the ground, the
object has both Gravitational Potential Energy and Kinetic Energy are
present.
Using the transfer of mechanical energy equation, the totalenergy at that
position is the sum of the two individual energies.
(PE + KE)
Slide 90 / 111
At position A in the diagram below, the roller coaster car has 40 J of
Total Energy and has a velocity equal to 0 m/s.
How much Kinetic Energy does the car possess at Point A?
0J
How much Gravitational Potential Energy does the car possess at
Point A?
40 J
40 J
15 J
25 J
Slide 91 / 111
At position B in the diagram below, the roller coaster car has a
Gravitational Potential Energy equal to 15 J.
How much Total Energy does the car possess at Point B?
40 J
How much Kinetic Energy does the car possess at Point B?
25 J
40 J
15 J
25 J
Slide 92 / 111
At position C in the diagram below, the roller coaster car has a
Gravitational Potential Energy equal to 25 J.
How much Total Energy does the car possess at Point C?
40 J
How much Kinetic Energy does the car possess at Point C?
15 J
40 J
15 J
25 J
Slide 93 / 111
31 At what position in the diagram below does the
object have only Gravitational Potential Energy?
A W
X
Answer
B
C Y
D Z
E
None of the above
h=0m
Slide 94 / 111
32 At what position in the diagram below does the
object have only Kinetic Energy?
A W
X
Answer
B
C Y
D Z
E
None of the above
h=0m
Slide 95 / 111
Answer
33 At what position in the diagram below does the object
have only Gravitational Potential and Kinetic
Energy?
A W
B
X
C Y
D Z
E
None of the above
h=0m
Slide 96 / 111
Transfer of Kinetic Energy to Elastic
Potential Energy
Kinetic Energy can be transferred into Potential Energy the same way.
What must be true is that the
Total Energy of the object
must be always the same.
Slide 97 / 111
Transfer of Kinetic Energy to Elastic
Potential Energy
In the top picture, the block is travelling
at 10 m/s, meaning that it has Kinetic
Energy. Because the spring is at the
relaxed length there is no Elastic
Potential Energy present. All of the
block's energy is Kinetic Energy.
In the bottom picture, the block has
compressed the spring and is no
longer moving, meaning the block has
no Kinetic Energy. All of the Kinetic
Energy has been transformed into
Elastic Potential Energy.
Slide 98 / 111
Answer
34 In which position of the block would the system
have only EPE?
A
B
C
Slide 99 / 111
Answer
35 In which position of the block would the system
have only KE?
A
B
C
Slide 100 / 111
A
B
C
Answer
36 In which position of the block would the system
have both KE and EPE?
Slide 101 / 111
What if the Total Mechanical Energy is not
equal at the beginning and the end?
If the total amount of energy that we start with, Ei, does not equal
the total amount of energy that we end up with, "Ef ", then
mechanical energy is not naturally conserved.
TEi = TEf
Because of this, the system is not a closed system, and the
surroundings are allowed to interact with the system. This means
that there is an outside for that is acting on the system over some
distance.
We talked about this in the last unit. What term did we use for the
energy used when a force acts over a distance?
Slide 102 / 111
Types of Energy Resources
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of Contents
Slide 103 / 111
Energy Resources
Electrical Energy can be produced through the Conservation of Energy by
using the Mechanical Energy contained in Energy Resources.
Energy Resources can be broken down into two categories: Renewable
and Non-Renewable.
Renewable Energy Resources are natural resources that can replenish
themselves over time.
Non-Renewable Energy Resources are natural energy resources that
exist in limited supply and cannot be replenished in a timely manner.
Slide 104 / 111
Types of Energy Resources
Slide 105 / 111
Energy Production from the Sun
Solar Energy is a renewable form of
energy that is produced when photons
that are contained in sunlight are
absorbed by specially designed plates
that are angled towards the sun.
When the photons hit the solar panels, charged particles are free to move which
causes a current to be produced. This current is converted to usable electricity
by the home.
Slide 106 / 111
Energy Production from the Wind
Wind is a renewable energy resource
that is used to create electricity by wind
turbines, such as in the Alta Wind
Energy Center in California, the world's
largest Wind farm.
As the wind blows past the blades of the
turbine, the Kinetic Energy of the wind is
transferred to the blades of a Wind
Turbine as they rotate. Inside the
column of the turbine there is a drive
shaft which is connected to a generator.
As the blades spin, the drive shaft converts the kinetic energy into mechanical
energy. A generator that is connected to the drive shaft then converts the
mechanical energy into electrical energy.
Slide 107 / 111
Energy Production From Water
Water is a renewable resource that can be used to
create electricity in dams such as the Hoover Dam.
Dams are used to convert the kinetic energy
possessed by moving water into electricity by
moving a turbine connected to a generator.
Slide 108 / 111
Energy Production From Water
The water at the top of the reservoir
possesses Gravitational Potential
Energy.
As the water moves through intake
and down the penstock, the water's
Gravitational Potential Energy is
converted into Kinetic Energy.
As the water moves past the turbine, the Kinetic Energy that the water
possesses is converted into Mechanical Energy as the turbine moves.
The Mechanical Energy that is created by the turbine is then transformed
into Electrical Energy by the generator.
Slide 109 / 111
Energy Production from Fossil Fuels
Fossil Fuels are a non-renewable energy
resource that can be used to produce electricity
when it is burned. Fossil Fuels include: Natural
Gas, Oil, and Coal (shown to the right). When the
fuel is burned the heat turns water into steam
which turn the blades of turbine producing energy
similar to the way that energy is produced in a
hydroelectric dam.
Slide 110 / 111
Effects of Using Fossil Fuels As An Energy
Resource
Fossil Fuels are Non-Renewable Energy Resources due to how long it
takes for them to be produced compared to how much is used to create
energy. Fossil Fuels take millions of years to be produced.
Fossil Fuels are also not considered "Clean" Energy resources as they
produce Carbon Dioxide (CO2) when burned. Carbon Dioxide is
considered a Greenhouse Gas, which many believe is a cause Global
Warming.
Slide 111 / 111
37 Which of the following is not considered a renewable
energy resource?
B Wind
C Hydroelectric
D Fossil Fuels
Answer
A Solar