2. Gravity is the force that pulls objects
towards the larger object. Earth is the
larger object that is why things on the
Earth fall down. Earth is big. The moon is
small that is why there is not as much
gravity on the moon. Gravity does not
make you unable to go up. You can jump
but you will fall back to earth. Over
longer distances things will fall faster.
The person on the moon can jump higher
than the goalie because gravity is not
pulling on him.
3. Friction is the force that
makes it harder to push or pull
things on a surface. If we didn’t
have friction if you touched
something it would go on
forever.
4. Simple Lever
Wedge
Machines Wheel and Axle
Pulley
Inclined Plane
Screw
5. A wedge helps split or go
though things. In the
picture the hammer hits
Wedge the wedge the wedge goes
though the wood. A wedge
splits the wood not
smashes it.
6. These are the three
different kinds of levers.
Levers help you lift
Lever something heavy. You can
use a shovel to prop a rock
out of the ground instead
of lifting it.
7. A wheel and axle is a wheel
connected to a pole. When
one rotates the other one
Wheel and Axle does too.
8. The picture to the left is a
block and tackle pulley. A
block and tackle helps lift
Pulley heavy loads.
9. On an inclined plane you
can slide the load up the
inclined plane. This has
Inclined Plane friction but is easier than
to lift it strait up.
10. A screw is an inclined
plane wrapped around a
pole. It helps go into
Screw things.
