learning about forces and motion

Genre Comprehension Skill Text Features Science Content
Nonfi ction Cause and Effect • Captions
• Labels
• Glossary
Forces and Motion
Scott Foresman Science 2.1
Standards
Preview
Standard Set 1. Physical Sciences
1. The motion of objects can be
observed and measured. As a basis for
understanding this concept:
1.a. Students know the position of an
object can be described by locating it
in relation to another object or to the
background.
1.b. Students know an object’s
motion can be described by
recording the change in position of
the object over time.
1.c. Students know the way to change
how something is moving is by giving it
a push or a pull. The size of the change is
related to the strength, or the amount of
force, of the push or pull.
1.d. Students know tools and machines
are used to apply pushes and pulls
(forces) to make things move.
1.e. Students know objects fall to
the ground unless something holds

them up.
1.f. Students know magnets can be
used to make some objects move
without being touched.
ISBN 0-328-23495-8
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by Kristin Cashore
Physical Sciences
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Vocabulary
attract
force
friction
gravity
motion
repel
Picture Credits
Every effort has been made to secure permission and provide appropriate credit for photographic material. The
publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.
Unless otherwise acknowledged, all photographs are the copyright of Dorling Kindersley, a division of Pearson.
Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd).
4 Getty Images; 13 Jerry Young/DK Images.
ISBN: 0-328-23495-8
Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America.
This publication is protected by Copyright, and permission should be obtained from the publisher prior to any
prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic,
mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to
Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.
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by Kristin Cashore
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Learning About
Position
Position is where an object is. How can you
talk about position? You can use words such as
behind and in front of to talk about position.
Look at the picture of the man and the girl.
The man is behind the counter. The girl is in
front of the counter.
The water is to the
left of the fruit. The
woman is behind the
counter.
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You can also use words such as left and right
to talk about position. Do you see the water on
the counter? It is to the left of the fruit. How can
you use left and right to talk about the fruit?
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How else can you talk about position? You
can talk about position based on something
that does not move. The background does not
change. The cabinets and stove do not move.
They are in the background of the picture.
Things in the

background can help
you talk about position.
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We measure things to learn more about
position. Look at the fl owers and lemons in the
picture below. Their positions can be measured.
The fl owers are 1 meter from the sink. The
lemons are 11 centimeters from the fl owers.
Use meters and
centimeters to
measure.
1 meter
11 centimeters
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Learning About
Motion
Motion is the act of moving. In what way
do things move? Some things move back and
forth. Some things move around and around.
Some things move in a straight line.
The boy in the picture moves back and forth
on the swing. The top spins around and around.
Your car moves in a straight line.
The cars move
in a straight
line.
The boy
swings back

and forth.
The top spins
around and
around.
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The speed of motion can change. If the boy
moves his legs more quickly, he will run faster.
The direction of motion can change. If the
boy on the bicycle turns the handlebars, the
bicycle changes direction.
Things move at different speeds. Look at the
picture. The boy ran for 10 seconds. The other
boy pedaled for 10 seconds. Who do you think
went faster? Who do you think went farther?
The bicycler traveled
faster and farther than
the runner.
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Force
An object needs a push or pull to move. A
push or pull that can make something move is
called a force.
An object will move in the same direction it
is pushed or pulled. It will not speed up or slow
down until it is given another push or pull.
The more force you use,
the farther the box will go!
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Pushing a wagon gently takes little force.
Pushing it harder takes more force. The cart
moves farther when you push it harder! It takes
more force to move objects farther.
It takes more force to move a heavy thing
than a light thing. Which wagon takes more
force to move? Read the caption to fi nd out!
It takes more force to
move the wagon with
the black dog.
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Learning About
Friction
What if you give a cart a push and let it go?
After a while, it stops moving. This is because
of friction.
Friction is a kind of pull. It makes a moving
object slow down or stop. The carts slow down
because of friction between them and the
ground.
The girl works against
friction to push the carts.
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Look at the skaters. The one on the smooth
road goes faster than the one on the sand.
There is a lot of friction between the skates and
the sand. This friction makes the skates slow

down. There is less friction between the skates
and the road. This allows the skater to go faster
on the road.
The skater
moves fast on
the road.
The skater moves
slowly on the
sand.
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Learning About
Tools and Machines
How do tools and machines help us? Tools
and machines use pushes and pulls to make
things move. Tools and machines can help us
do hard things!
A hammer is a tool. It
uses force to drive in
the nail.
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See the picture? A wooden spoon is a tool. It
pushes the food. It helps mix the eggs and fl our.
A truck is a machine. Its engine uses force.
The force spins the truck’s wheels. Then it can
move the heavy logs.
A truck is a machine. A truck
helps us move heavy things.
The spoon helps mix

the meal. It is a tool.
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Learning About
Gravity
Look at the picture. The boy is shooting the
ball. What will happen? Will the ball fl oat into
the sky? Will it land on the ground?
Gravity will pull the ball down to the
ground. What is gravity? Gravity is a pulling
force. It pulls things toward Earth’s center.
When you jump up, you come back down.
Gravity is what makes you come back down.
Gravity pulls the ball
toward the center of
Earth.
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What does it mean if something is heavy? It
means the pull of gravity on that thing is strong.
Gravity pulls harder on heavier things.
The ball weighs more than the apple. Gravity
pulls harder on the ball than on the apple.
Gravity pulls harder on
heavy things than on
light things.
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Learning About
Magnets

What is a magnet? A magnet is a special
object that creates a force. Magnets can push
some kinds of metal.
The letters and numbers on the
refrigerator door are magnets.
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Magnets attract some metal objects. To
attract is to pull toward. Look at the picture.
The paper clips are made of metal. The magnet
attracts them.
Magnets can attract or repel other magnets.
To repel is to push away.
This magnet has
attracted several
paper clips.
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Magnets have poles. The pole is the part of
the magnet that has the strongest push or pull.
Look at the magnets in the picture. The north
pole is marked with an N. The south pole is
marked with an S. Each magnet has a north
pole and a south pole.
The N and S on a
magnet show where
its poles are.
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Opposite poles attract each other. Like poles

repel each other.
Magnets can move some objects without
touching them. Look at the picture. The magnet
is not touching the lock. But the magnet is
pulling the lock!
The magnet attracts
the metal of the lock
without touching it.
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attract pull toward
force a push or a pull that makes
something move
friction a pull that makes a moving
object slow down or stop moving
gravity a force that pulls things toward
the center of Earth
motion the act of moving
repel push away
Glossary
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What did you learn?
1. What will happen if you put the like poles of
two magnets together?
2. Does gravity pull harder on a bowling ball or
a feather? How do you know?

3.
Look at the classroom
around you. Think about position. Write to

explain the position of at least two things in
the classroom. Use words such as behind, in
front of, left, right, or background.
4. Cause and Effect You throw a ball into
the air. What caused it to move? What effect
does gravity have on the ball?
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