Define force.
A push or pull.
Define gravity.
A force that pulls objects toward Earth's surface.
What force does a seesaw use?
Up and down
Define motion.
The process of an object changing positions.
Define oppose.
To work against.
What force does a tetherball use?
Around and around
Define a push and a pull.
Push - a force to move something away from you.
Pull - A force to move something closer to you.
What is a force that occurs between the surfaces of two objects that are touching?
Friction
What force does a pendulum use?
Back and forth
What is a collection of forces acting on an object that cancel each other out and produce no change in the object's motion called?
Balanced forces
Define contact force.
A push or pull between two objects that are touching each other.
To say that something is expected to happen.
What is a collection of forces acting on an object that result in a change in the object's motion called?
Unbalanced forces
What is the name of the a substance that reduces friction between objects in contact?
Lubricant
Define pattern.
Something that keeps repeating