A magnet has two __________, north and south.
poles
An __________ is a ramp that we use to move objects up and down. It reduces the force we need to push an object.
inclined plane
__________ is a force that occurs when two objects rub against each other. It slows down moving objects.
Friction
Are the machines in the picture simple or complex?
They are simple machines.
Some objects, like a sponge, change shape __________. They return to their original shape when the force stops acting on them.
temporarily
___________ is a force that attracts some metals. It flows from the north pole to the south pole.
Magnetism
The same poles of two magnets __________ each other.
repel
The fixed point in a lever is called a __________ or a __________.
fulcrum, pivot point
Some objects break when a lot of force is applied to them. These are __________ objects.
rigid
The opposite poles of two magnets __________ each other.
attract
__________ is a force that pulls objects down towards Earth. We see the effct of this force when an apple falls from a tree.
Gravity
__________ can make an object start moving, stop moving, change shape or break.
Forces
A simple machine has __________ parts, but a complex machine is made of many parts.
only one or a few
A __________ is a simple machine that turns on a fixed point and makes it easier to lift heavy objects.
lever
Some objects, like clay, change shape __________ when a force is applied to them. They keep their new shape.
permanently
Some forces can act on an object at a distance. These are called __________. For example: gravity and magnetism.
non-contact forces