Page 1
Move It!
Turn up the music and let's
dance! Jump up and down.
Shake side to side.
Your body shows just
how many kinds of
motion there are. Motion is
another word for moving.
Page 2
The Importance of Force
What puts things in motion? Crack! A swinging bat sends a
baseball flying. Vroom! An engine powers a car.
Your muscles get your body going.
Page 3
A swinging bat, an engine, and your muscles
provide force. Things never move by themselves.
It takes force to get them moving.
Page 4
Whoops! You hit your glass and it crashed
on the floor. What force pulled your glass
to the ground? Gravity is the force that
pulls everything down to the ground.
Page 5
Turning and Stopping
You are riding your bike. Watch out!
A tree is in your path. What do you do?
You turn your handlebars.
Things in motion do not change
direction by themselves.
It takes a force to make
them turn.
Page 6
Uh-oh. This time a fence is blocking your path.
Things in motion do not stop by themselves.
It takes a force to make them stop.
Page 7
Friction
But wait a minute! You boot a soccer ball
across a field. Nobody touches it, but it still
rolls to a stop. What happened?
The ball rubbed against the grass
and friction was created. Friction is
the force that stopped the ball.
Page 8
Air rubs against moving things, too. This creates
a type of friction called air resistance. Air resistance
is very powerful. It can slow down
a car, a plane, or even a rocket.
Page 9
Make It Fast!
Imagine you are inventing a car. How will you make it go fast? You'll need a powerful source of force. The more force, the faster things go.
Page 10
What will you use to make your car? Your decision will
affect the car's speed. Heavy materials will slow your
car down. It takes more force to move
heavy things than it does light things.
Page 11
Tricky Motion
Motion can be tricky.
Think about what you
do to make a scooter
go forward. You push
backward with
your foot.
Page 12
Let's say you're sitting on a train. The people around you do not look like they are moving.
Page 13
But from outside the
train, you would see
that the whole train
was speeding by.
Page 14
Sometimes you can't even tell you're moving. Our Earth is spinning like a top. It's circling the sun. Do you feel it?
Page 15
Spinning and scooting, zooming and springing,
motion is all around. Isn't it marvelous?
