potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
SciGen Unit 8.1
science
POTENTIAL AND
KINETIC ENERGY
SCIENCE ACTIVITIES
Session 1
2–5
Session 2
6–11
Session 3
12–13
Session 4
14–16
Session 5
17–19
Reader’s Theater
Speaking Scientifically
In the Lab
Getting a Grip on Gravity
Writing
SUPPLEMENTARY ACTIVITIES FOR OTHER
CONTENT AREAS
ELA
20
Math
21
Social Studies
22
The Gravity of Gravity
Speed vs. Velocity
History of the Roller Coaster
FOCUS WORDS
Examining the Focus Words Closely
© 2015 SERP
SciGen Unit 8.1
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1
Session 1
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
SpeakingTheater
Reader's
Scientifically
Keeping Track of Energy
Setting: Cooper, Olivia, and Hamza had a hard time with their science homework last night. They’re talking in the
hallway before class.
Cooper: You look half dead, Hamza. Here, take my
energy bar.
Olivia: Whoa, there’s a lot going on there. It’s confusing.
It’s like everything is all connected. How can you even
keep track of what you’re talking about?
Hamza: Thanks. I get that the bar will give me some
energy, but I did not get last night’s homework about
energy. Did you?
Olivia: Hi guys! I thought the homework was confusing,
too. It said something about energy having to do with
things moving, but energy bars don’t move. At least not
like a ball or a wave does.
Hamza: The fan is winding up the thing attached to the
stand. When you turn the fan off the mass is going to
drop back down because of gravity. What a crazy setup.
Cooper: Maybe they’re called energy bars because they
can make people move more when they eat them? I don’t
know, though.
Hamza: I thought energy was electricity that makes stuff
work, like lights.
Olivia: Maybe energy can do a lot of different things. But
then why bother with the word “energy”? Why don’t we
just say “food” when we mean food and “electricity” when
we mean electricity?
Hamza: I think that this energy bar is working. I feel
better. My energy had gone on vacation, and now
it’s...coming home.
Cooper: You know, your energy might have come back,
but the energy we are studying never goes away, it just
changes. Look...
He pulls out his homework and points to this graphic:
Olivia: You totally could have done your homework if
you’d tried. You got that way faster than I did. So this
weird energy system is storing up energy as the string
gets wound up.
Cooper: Yeah. The kinetic energy involved in the winding
up is getting switched over to potential energy.
Hamza and Olivia: Huh?
Cooper: Remember how the energy of the sliding book
was slowed down by friction so the table and the book
got hotter? Well, probably just a little hotter. Anyway,
that’s where the energy went, into heat.
Olivia: Are you saying that hotter people use more
energy? Well, that means that Hamza...
Olivia: I said that? Uh, I mean thanks, Ms. Q!
Hamza: (cutting her off) Don’t go there, Olivia.
Cooper: (changing the subject) Look at the next picture.
We’re supposed to explain what’s going on in terms of
energy.
© 2015 SERP
Ms. Quintanilla: Sorry, guys. I couldn’t help
eavesdropping because I was so impressed with your
comments. Especially yours, Olivia, about the challenge
of keeping track of different parts of a system.
Ms. Quintanilla: System is a great word in science
because it’s flexible. It’s like drawing an imaginary
boundary around a portion of the real world and studying
how the parts within it work together. Let’s look at the last
part of your homework with that hillside problem.
SciGen Unit 8.1
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Session 1
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Reader's Theater
Keeping Track of Energy
Hamza: That was hard!
Ms. Quintanilla: It’s supposed to be hard. When things are easy you’re not really learning, you’re just performing.
Remember that these exercises were supposed to help you begin thinking about energy. If you’re struggling, that means
you’re thinking! We’ll discuss them right now in class.
Hamza: Oh good. I’m glad. I didn’t understand what you meant by potential and kinetic, either.
Ms. Quintanilla: Excellent question. We’ll go over that as well.
They all walk into the classroom. Ms. Q asks the class to look at five images of the hillside (part of their homework). She
tells the members of each table group to compare answers and to discuss their thinking. Cooper, Hamza, and Olivia are
sitting at the same table, and they all have different answers to the problem. Here’s how the problem looked on their
worksheet:
The five illustrations show an energy system but they aren’t in the correct order. Think through how the energy would move
through this system. Then cut out the the images and tape them on another piece of paper in the correct order.
Ms. Quintanilla: In fact, we can use these little pictures to help us with a few more helpful terms we need to learn:
momentum, acceleration, velocity, and inertia.
Olivia: I hear the first two of those words all the time. Our lacrosse coach talks about momentum a lot.
Hamza: And you hear about acceleration in car commercials.
Ms. Quintanilla: Great! Well, let’s talk about the science so you can see why coaches and advertisers like the terms so
much.
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Reader's Theater
Keeping Track of Energy
Ms. Q draws on the whiteboard:
Something that’s moving has
momentum.
Velocity is how quickly something is
moving in a particular direction.
Acceleration describes
how the velocity is
changing.
Inertia is the tendency for objects at rest
to remain at rest (OR to keep traveling at
the same velocity if they are traveling).
Cooper: (under his breath) I’m glad she’s our science teacher and not our art teacher...
Ms. Quintanilla: (to the entire class) My extra credit starter challenge for you all today is to look at the last problem of
your homework, the one with the hillside, and to add a caption that describes what’s happening in the sequence. But
try to use the terms I’ve written on the whiteboard correctly as you write.
Hamza: Extra credit? Awesome. This will help make up for the other times when I didn’t have the energy to do my
homework.
Olivia: I say again Hamza, not an energy problem...an attitude problem.
Hamza: Whatever.
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Reader's Theater
Comprehension Questions
Below are clippings from Hamza’s, Cooper’s, and Olivia’s homework assignments. Evaluate their sequences and
captions and then answer the questions about their work.
Here is Hamza’s sequence:
Here is Hamza’s caption: The ball on top of the hill is still because of inertia. The ball’s velocity increases as it goes down
the hill. The block stops the momentum of the ball so it’s not accelerating.
Would you change Hamza’s sequence? yes | no
How would you improve Hamza’s caption? _________________________________________________________
___________________________________________________________________________________________
Here is Cooper’s sequence:
Here is Cooper’s caption: The ball had lots of momentum, so there’s a big BUMP because inertia would cause the block to
want to stay still and the ball to keep rolling. The second time the ball hit the block there’s less velocity because it did not
roll down the whole hill.
Would you change Cooper’s sequence? yes | no
How would you improve Cooper’s caption?_________________________________________________________
__________________________________________________________________________________________
Here is Olivia’s sequence:
Here is Olivia’s caption: The velocity increases and that is acceleration. The block doesn’t move very much when it is hit
because of inertia and friction.
Would you change Olivia’s sequence? yes | no
How would you improve Olivia’s caption? __________________________________________________________
__________________________________________________________________________________________
© 2015 SERP
SciGen Unit 8.1
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Session 2
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
Kinetic vs. Potential Energy
Energy surrounds us and is part of everything we do. It’s so common that it can be difficult to talk about. One way to help
us understand energy is to sort things with energy into two big categories.
I. Kinetic Energy:
the energy of motion.
II. Potential Energy:
the energy of relative position or shape.
This ball has kinetic energy because it is moving.
The word “kinetic” in English comes from the Greek
word kinetikos (moving).
Look around you right now. List three things with kinetic
energy and compare your answers with someone else
in the class.
__________________________________________
__________________________________________
__________________________________________
What did you see? A tree branch swaying outside the
window? The second hand on the clock? Or perhaps
the heads of other students turning about looking for
examples of kinetic energy?
© 2015 SERP
SciGen Unit 8.1
This ball has potential energy. It’s not moving
right now, but it could if the girl let go of it. The
ball’s position relative to the Earth has given it
potential energy.
Potential energy is all around you too, but it
might be a bit harder to spot. Do you see
anything with potential energy around you?
Anything that is inflated? Propped up? Hanging?
Usually these are examples of things that are not
moving but could if something happened. They
have the potential to move.
List three things with potential energy.
______________________________________
______________________________________
______________________________________
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Session 2
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
Kinetic Energy (KE) and Potential Energy (PE) Within a System
3
2
1
Sometimes objects have both kinetic and potential energy. Let’s say that Child #1 is just sitting on the swing and not
moving at all. Child #2 is moving backward. Her position moments ago was just like Child #3. Speaking of Child #3, he is
at the very highest point of his swing.
TURN AND TALK
Of the three children swinging, which is displaying the most kinetic energy? The most potential energy?
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
Transfer of Kinetic Energy (KE) and Potential Energy (PE) Within a System
A pendulum might help you better understand how kinetic and potential energy are both present in the swing set on
the previous page.
To make a pendulum:
Tie a metal washer to the end of a 50-cm
piece of string.
Hold the pendulum at the non-washer
end.
Ask another student in your class to give
the pendulum potential energy by
moving the washer about 30 cm to the
right or left.
Have your helper let go of the washer so
it can swing.
TURN AND TALK
Energy transformations are taking
place here.
1. Where?
2. When?
3. What happens if you just
let the pendulum swing for
awhile?
4. What happened to the
energy?
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
About the Pendulum and Its Energy
When your partner moved the washer to the left or right from its resting position, he or she gave the pendulum potential
energy. It was potential energy because the washer could swing due to its relative position and gravity. This kind of
potential energy is known as gravitational potential energy.
What’s interesting about a pendulum, though, is that when you let go of it, the potential energy gradually transforms into
kinetic energy. And then it gets faster and faster until it reaches the lowest point of the swing. At that point the kinetic
energy starts transforming back into potential energy on the other end of the swing. Then, the pendulum actually comes
to a stop! It comes to a stop for a very short time at the end of each swing. When it is “at rest” the energy is once again
potential energy.
With this great system going, you might think the pendulum would never stop. But as you observed, it does indeed stop
swinging after a while. But why? Where did all that energy go?
TURN AND TALK
What on Earth is this weird-looking graph trying to tell us?
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
Friction
The washer (and the string) is actually banging into something as it swings. But what? AIR MOLECULES, of course!
Swing your hand back and forth and feel them for yourself! But an even more significant reason for the pendulum
slowing down is the friction between the string and your fingers and the friction of the different parts of the string itself.
TURN AND TALK
What on Earth is this even weirder-looking graph trying to tell us?
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Speaking Scientifically
Try It Out!
Check the appropriate box next to each image. KE stands for kinetic energy. PE stands for potential energy. Don’t
hesitate to check the “unsure” box. Not knowing the answer right away is a GOOD thing in science class!
PE
PE
KE
KE
both
both
unsure
unsure
PE
PE
KE
KE
both
both
unsure
unsure
PE
PE
KE
KE
both
both
unsure
unsure
TURN AND TALK
Compare your responses with someone else in your class. Discuss.
© 2015 SERP
SciGen Unit 8.1
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Session 3
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
In the Lab
Rubber Band Lab:
Can you use measurements to study the relationship between potential and kinetic energy within a system?
You will need:
•
a rubber band
•
a Styrofoam or paper cup sliced in
half lengthwise
•
a ruler
How to cut a cup in half lengthwise...
Procedure:
1.
You will stretch your rubber band 3 different lengths – short stretch, medium stretch, and long stretch. Each length
of the rubber band is a “condition” of your experiment.
2. Conduct 3 trials for each condition.
3. For the 3 trials for each condition, make sure the rubber band is stretched exactly the same length and that the
cup starts in the exact same place.
4. Carefully aim the rubber band at the same spot on the cup (so the cup will move in the same direction).
5. Record how far the cup moves for each trial. Then calculate the mean distance for each of the 3 conditions.
Condition 1
(short stretch)
Condition 2
(medium stretch)
Condition 3
(long stretch)
Potential energy (represented by
rubber band stretch):
Potential energy (represented by
rubber band stretch):
Potential energy (represented by
rubber band stretch):
Length of rubber band stretch =
______ cm
Length of rubber band stretch =
______ cm
Length of rubber band stretch =
______ cm
First Trial:
Cup moved ______ cm
First Trial:
Cup moved ______ cm
First Trial:
Cup moved ______ cm
Second Trial:
Cup moved ______ cm
Second Trial:
Cup moved ______ cm
Second Trial:
Cup moved ______ cm
Third Trial:
Cup moved ______ cm
Third Trial:
Cup moved ______ cm
Third Trial:
Cup moved ______ cm
Kinetic energy (represented by
cup movement):
Kinetic energy (represented by
cup movement):
Kinetic energy (represented by
cup movement):
mean cup movement =
______ cm
mean cup movement =
______ cm
mean cup movement =
______ cm
© 2015 SERP
SciGen Unit 8.1
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Session 3
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
In the Lab
Analyzing your data from the Rubber Band Lab
Restate your results here. Then graph them below.
Condition 1: When the rubber band was stretched ________ cm, the cup moved an average of ________ cm.
Condition 2: When the rubber band was stretched ________ cm, the cup moved an average of ________ cm.
Cup movement
Condition 3: When the rubber band was stretched ________ cm, the cup moved an average of ________ cm.
Rubber band stretch
TURN AND TALK
Do you see a trend? Do these data support any ideas you might have about the relationship of potential and
kinetic energy in this system?
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Session 4
Getting a Grip on Gravity
All through history people have asked the same questions,
like “What's for dinner?” and “Why do things fall?” Aristotle,
who lived in Athens almost 2,500 years ago, argued that
the center of the Earth was the center of the universe. So
naturally everything tended to fall in that direction! Wrong
on TWO counts. He also thought that heavier things fell
faster than lighter things. Well, you could see how he would
think that. Try dropping a piece of paper and a book. The
book hit the floor first, right? But not because of gravity and
not because it is heavier.
Gravity n.
A force that acts betwee
n all masses,
pulling them together.
Is the definition helpful?
Sort of.
Not really.
Seriously?
WHAT?
Here is where Galileo comes in. He carefully dropped balls
from towers and rolled them down inclines. He stated that
the reason your book drops faster than your paper is not
due to their difference in mass, but rather because air
resistance (friction) affects the falls differently.
Explore Galileo’s idea.
Step 1: Go to the moon.
Step 2: Drop a feather and a hammer at the same time.
Oh, going to moon is not in your budget? Well, watch this
video of two astronauts who tried it out:
http://wordgen.serpmedia.org/apollo.html
(Thanks for the video, NASA!)
As great as Galileo was, Isaac Newton was the one who
really hit it out of the park with this idea: He said that gravity
is not just about the Earth pulling things, but rather that
everything that has mass creates a gravitational force.
© 2015 SERP
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Session 4
Getting a Grip on Gravity
Consider an apple and the planet Earth.
Newton said that the apple is pulling on the Earth in exactly the same
way as the Earth is pulling on the apple.
Huh?
Then, you might ask, “Why doesn’t the Earth fall up to the apple?” Well,
the answer to that is...
It does.
Huh??
Just not very much. Actually, it’s an immeasurably small distance.
So, how can the apple and the Earth react to equal forces so differently?
To understand this, think about applying an equal force to two things with very different masses.
1. Think
about
flicking a
paper clip
with your
fingers.
2. Think about
flicking a
parked car
with your
fingers.
!
!
Why wouldn’t the car move as much as the paper clip??
INERTIA.
Massive things have more mass (duh!), more gravitational force, and more inertia. If you think that car was hard to move
with a flick of your fingers, just imagine how tough it would be for the apple’s gravitational field to yank the Earth up to it.
Not gonna happen!
LAST question: The acceleration of the apple dropping to the Earth is
◻ greater than
◻ less than
◻ about the same as
But why?
the acceleration of the Earth up to the apple.
© 2015 SERP
Greater than, of course!
You can definitely observe
that.
SciGen Unit 8.1
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Getting a Grip on Gravity
Gravity causes the apple to move toward the Earth and yes, the Earth to move toward the apple (good luck observing
the latter). You can measure movement (of the apple at least) using velocity. If the velocity changed along the way, you
can describe that as acceleration. The apple’s fall to Earth started slow and got faster. There is all kinds of interesting
math about the details of that. Ask your science teacher to explain more if you’re interested. But don’t get carried away.
You have to save something for high school!!
The important thing here is to remember that when we think about gravity, it’s easy to think about it as the Earth pulling
on things. And that’s true. The Earth does, indeed, pull on things. But keep in mind that everything else that has mass
pulls on things, too. The Earth tends to get our attention the most because it’s the biggest thing around pretty much
everywhere we hang out!
If you compare the Earth to the Sun, the Earth is a little more like the
apple in that situation. The Earth is affected by the Sun’s gravity in a
major way, but also by all sorts of other interesting forces in the
universe. (Good thing, too...or we’d be toast! Burnt toast at that!)
© 2015 SERP
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Session 5
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Writing
Scripting a Demonstration for Younger Students
The second coaster might seem safer, but...
You’re taking your little cousin to the amusement park for the day and it’s your job to keep him safe. You really want to
go on the roller coaster, and he says he really wants to as well. But you predict that when he sees how tall the roller
coaster is at the park, he may back out. He’s always afraid of getting hurt. Thinking ahead, you draw the pictures
below for him to make a point that sometimes taller and faster is better.
Think about what you now know about potential energy. Is there more potential energy in the car poised at the top
of roller coaster A or in the car at the top of roller coaster B? If you answered A, you’re right! And roller coaster A uses
more kinetic energy and momentum to get through the entire ride safely. Though roller coaster B LOOKS less scary,
the truth is that it might not have enough energy to get through the loop. Riders might not make it all the way to the
end of the ride!
Roller Coaster A
Roller Coaster B
54 m
35 m
35 m
39 m
A drawing is a great way to make a model, but here is another idea to really help your little cousin understand.
54 m
35 m
Supplies used to make this model:
Plastic tubing from the hardware store
Marble
Ruler
,
.
, ,
,
,
,
35 cm
© 2015 SERP
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potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Writing
Scripting a Demonstration for Younger Students
It’s your turn to share your knowledge about roller coasters and
energy with a classroom of second graders. Your goal is to make sure
the students understand that roller coaster A is safer than roller
coaster B and why. How will you explain this in a clear, simple way?
You might want to create a simulation, like the one on the previous
page, to make it easier for the kids to grasp the concepts. Or feel free
to come up with another fun and effective way to convey your
information. Write a script as if you are speaking directly to the
students. Don’t forget to introduce yourself!
Roller Coaster A
Roller Coaster B
Explanation for younger students:
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
© 2015 SERP
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Writing Prompt
Writing for a Different Audience
Roller Coaster A
Now provide the same explanation as on the previous page, but
for a different audience. For example, write as if this roller coaster
question is on the application to the high school you would like to
attend.
Roller Coaster B
Explanation for high school application:
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
© 2015 SERP
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ELA
The Gravity of Gravity
The language of science is powerful. Words used to describe the forces that help us make sense of our universe have a
unique place in the world of words. When used in poetry or creative writing, they’re able to move us, challenge us, and
change us because they connect us to something much bigger than ourselves.
Think of the word “gravity.” The nonscientific meaning of the word is “seriousness” or “importance.” But how heavy the
word feels! We can’t help but imagine, either consciously or unconsciously, the pull of planets, that tremendous force
that influences how Earth orbits the Sun.
Consider an experience you’ve had that was
emotionally or physically intense. Maybe someone
you really thought you could depend on
disappointed you? Or you found yourself in a
situation that pushed your body to the limit? Now
see if you can write about it, either in poetry or
prose, using one or more of the focus words
below.
‣
gravity
‣
kinetic
‣
friction
‣
momentum
‣
velocity
‣
acceleration
‣
inertia
‣
potential
If you’d like, see if these additional words inspire
you. Scientifically speaking, they describe forces
and the different ways that forces can make an
object change shape. But they have other
meanings, too, which you’ll probably recognize.
‣
distortion
‣
tension
‣
stress
‣
compression
‣
strain
Having trouble? Need a jumpstart? Try writing an
acrostic poem. Choose a word and then write it
down vertically. Let each letter be the beginning of
a word. Feel free to add more words per letter or
get creative in other ways.
© 2015 SERP
An acrostic poem using the word “friction”:
Finally,
Rain comes.
I’m
Crying
Twice as much as the
heaviest downpour.
I can’t believe you
Only closed the door.
No goodbye.
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Math
Speed vs. Velocity
Are we splitting hairs, or is there really a difference?
Speed is a type of rate that measures how long it takes to travel a distance.
Velocity measures how fast something is moving plus the direction that the object is moving. So a car driving from
Baltimore, Maryland, to Norfolk, Virginia, might have a velocity of 70 miles per hour south.
Consider this:
On Monday, you rode your bike on the direct road from point A to point B in exactly one hour without stopping.
On Tuesday, you rode your bike on the curvy road from point A to point B in exactly one hour without stopping.
Did you ride your bike at a greater average speed on one of the roads? Absolutely!! The curvy one!
Tuesday route
Point A
Monday route
Point B
TURN AND TALK: How do you know?
Here’s the weird part: Your overall (or average) velocity
on Monday and Tuesday is the same. But how can that
be? It’s because you measure average velocity using
only the start and end points and by referring to
direction. So if Point B is 15 miles east of point Point A,
that means that your average velocity was 15 miles per
hour east.
Here’s another problem to think about:
On Wednesday, you rode your bike at 15 miles per hour from Point A to Point Y. On Thursday you rode your bike at 15
miles per hour from Point A to Point Z. That means that you traveled at the same speed on both Wednesday and
Thursday. Right? Right.
But in this case, the average velocity is not the same.
TURN AND TALK: Why is the average velocity different?
Point A
Point Y
Point Z
© 2015 SERP
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Social Studies
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
History of the Roller Coaster
The modern roller coaster descended from towering ice slides in Russia, which first appeared in the 17th century.
Referred to as “Russian Mountains,” these slides provided entertainment throughout Russia, though they were most
prevalent in the area that would later be known as St. Petersburg. Rising up between 70 and 80 feet in the air, the slides
were made from lumber that was covered with several inches of ice and offered riders an exhilarating 50 degree drop.
The slides were reinforced with wooden supports and had steps up the back for riders to climb before speeding down
on sleds. Popular with the upper class, some slides were ornately decorated. An enthusiastic fan of the slides, Catherine
the Great reportedly had several built on her property.
Historians debate who deserves credit for adding wheels and creating the roller coaster as we know it. Some contend
that the Russians invented the first roller coaster, which was constructed in the Gardens of Oreinbaum in St. Petersburg
in 1784. Other historians argue that the French are responsible for the first roller coaster. Les Montagnes Russes à
Belleville (The Russian Mountains of Belleville) was built in Paris and had many of the features we associate with the
modern roller coaster, including guide rails, cars with wheels that lock to the track, and plenty of speed. It is also likely
that Paris was home to the first permanent loop track, built in 1846 from an English design, and referred to as a
“centrifugal railway.” It was constructed
with a wheeled sled, which held one
person and traveled through a 13-foothigh vertical loop.
In the 1820s, the United States made an
impact on the development of the roller
coaster. A mining company in Summit Hill,
Pennsylvania, created an 8.7-mile
downhill track in order to deliver coal to
the town of Mauch Chunk. When the mine
closed in the early 1870s, the track was
dubbed "Gravity Road" and continued
offering rides to thrill-seeking visitors for a
price. A Sunday school teacher from
Ohio, LaMarcus Adna Thompson,
believed in the potential for wholesome
fun that this type of entertainment could
provide young people. He began to work
on his own gravity switchback railway. In
1884, Thompson’s Gravity Pleasure
Switchback Railway opened in Coney
Island, and America’s first true roller
coaster was born!
LaMarcus Thompson’s Switchback Railway (1884)
Activity
You and your partner are going to simulate an interview. Pretend the interviewer is a historian from a distant galaxy who
is working on a report about Earth, but he or she is completely confused as to why Earthlings would invest in roller
coasters. The role of the person being interviewed is an eighth-grade student who loves roller coasters and knows
about potential and kinetic energy. He or she attempts to explain why they are fun. The interviewer seems to
understand the science, but not the fun part. The eighth grader tries to connect the two.
© 2015 SERP
SciGen Unit 8.1
22
Focus Words
potential • kinetic • friction • momentum • velocity • acceleration • gravity • inertia
Examining the Focus Words Closely
SciGen Unit 8.1
Scientific or
Everyday Use
Definition
Try using the word...
potential energy
noun
the energy an object has
because of its relative position
What objects around you have potential energy?
potential
noun
possibility, such as talent or
skill that may be developed
later
Do you have the potential to become an athlete? A
musician? A scientist?
kinetic energy
noun
the energy of motion
The kinetic energy of falling water can grind wheat into
flour, saving human effort. Can you think of something
else powered by kinetic energy?
kinetic
adjective
relating to motion
Kinetic works of art, such as mobiles, are very popular.
Can you think of other examples?
friction
noun
the force slowing the motion
of objects due to interactions
along their surfaces
Do you think there is more friction with a steel wheel on
a train track or with a rubber tire on asphalt?
friction
noun
a conflict between people or
personalities
Describe a situation that might cause friction between
two students.
momentum
noun
the quantity of motion of a
moving body (mass x velocity)
How does a roller coaster’s momentum enable it to
climb hills and complete loops?
momentum
noun
a driving force in a process
If you fell behind in a competition, how would you
motivate yourself to gain enough momentum for a
comeback?
velocity
noun
the speed in a certain
direction
Explain a situation in which velocity changes even
though speed stays constant.
acceleration
noun
the rate of change of velocity
per unit of time
A roller coaster train accelerates as it descends. Why?
accelerate
verb
to gain speed; to make
something happen faster
Name some technologies that help accelerate
processes in your daily life.
gravity
noun
a force that acts between all
masses, pulling them together
Everything that has mass has a gravitational field. Why
is Earth’s gravity the most obvious to us?
gravity
noun
extreme or alarming
importance; seriousness
When might the gravity of a situation cause a
bystander to intervene?
inertia
noun
the property of matter by
which things continue their
current motion (either going
straight at the same speed or
staying still), unless a force
acts upon them
More massive things tend to have more inertia. Can
you think of an example?
inertia
noun
the tendency to remain
inactive or unchanged
Sometimes people blame inertia for the public’s
reluctance to invest in cleaner technology. Do you think
this is a fair assessment? Explain.
© 2015 SERP
SciGen Unit 8.1
23