Pushes and pulls
Back and forth, up and down. Swinging in a swing is almost like flying.
What makes the swing go up in the air?
Most of the time you do. You \”pump” with your legs and body. Sometimes
you can get a friend to push you. And sometimes you see the empty swing
moving when the wind pushes it. But something—you, your friend, or the
wind—has to give it a push. The swing can’t move by itself.
Anytime a thing moves, something makes it move. Something pushes it,
the way you, your friend, or the wind pushes the swing. Or something
pulls it, the way you pull a wagon or a sled. The push or the pull that
makes a thing move is called a force.
Seesaws and swings, roller skates and bicycles all get their force
from you. Pushes from your hands and feet make them move, carrying you
up and down through the air or whizzing you along on the ground.
