Motion

1. Friction

1.1. A force that opposes motion and that occurs when things slide or roll over each other

1.2. something sliding

1.3. the force opposes motion that happens when things slide or roll

2. Acceleration

2.1. The rate of change of velocity

2.2. the rate of change and velocity

2.3. the first law of motion

3. speed

3.1. The rate at which the position of an object changes

3.2. to time how fast something is

3.3. timing a runner

4. Distance

4.1. The length of the path between two points

4.2. how far something travled

4.3. how far the runner went

5. Time

5.1. The length of time that passes from one event to another

5.2. time passed from one time to another

5.3. the time a airplane takes off to when it lands

6. Volcity

6.1. the speed and direction in which an object is moving

6.2. speed and direction to show an object is moving

6.3. a car going from work to the store

7. Gravity

7.1. the force of attraction between any two objects that have mass

7.2. the force of contact between two objects that have mass

7.3. a rock on the ground

8. Force

8.1. push or pull

8.2. pull or pushing something

8.3. moving a box