1. Motion and Force

2. Force
A push or pull that causes an object to move, stop, or change direction

3. Friction
A force that opposes, or acts against, motion when two surfaces rub against each other

4. Velocity
An object’s speed in a particular direction

5. Speed
A measure of the distance an object moves in a given amount of time
During a typical trip to school, your car will undergo a series of changes in its speed.

6. Acceleration
A change in motion caused by unbalanced forces or a change in velocity

7. Gravitation
The force that pulls all objects in the universe toward one another

8. Mass and Weight The amount of matter in an object
A measure of the pull of gravity on an object