2. Motion and Force Chapter Twelve: Distance, Time, and Speed
Chapter Thirteen: Forces
Chapter Fourteen: Force and Motion

3. Chapter Twelve: Distance, Time, and Speed
12.1 Distance, Direction, and Position
12.2 Speed
12.3 Graphs of Motion

4. 12.3 Graphs of Motion
A position vs. time graph that is a straight line always means the object moves the same distance during each time period.

5. 12.3 Graphs of Motion
You can use position vs. time graphs to compare the motion of different objects.
The steeper line on a position vs. time graph means a faster speed.

6. 12.3 Slope The steepness of a line is measured by finding its slope.
The slope of a line is the ratio of the “rise” to the “run”

9. 12.3 Graphs of changing motion
Objects rarely move at the same speed for a long period of time.
A speed vs. time graph is also useful for showing the motion of an object that is speeding up
or slowing down.

10. Technology Connection
Roller Coasters: The Physics Behind the Thrill
That first roller coaster was all wood and ran in a straight line.
Roller coasters are now made of wood or steel, and the tracks include a variety of twists and turns and loops and drops that make the ride scary and thrilling.

11. Motion with Changing Speed
Investigation 12B
Motion with Changing Speed
How do we describe motion for which the speed is not constant?