1. Speed-Time Graphs
Speed
Time

2. Remember Distance-Time Graphs?
Speed
Distance
Time
With distance on the y axis and time on the x axis we could measure SPEED

3. Speed Time Acceleration
Speed-Time Graphs
Speed
Time
Acceleration
When the y axis is speed, (and x is time) we can calculate the acceleration!

4. So… for a Speed-Time Graph…
What is on the x axis?
Time
What is on the y axis?
Speed
What can we find using a speed-time graph?
Acceleration

5. An Object at Rest An object at rest is not moving, so its speed is 0
The speed-time graph for an object at rest is a horizontal line at y=0

6. Constant Speed
The speed is a number, but doesn’t change

7. Speeding Up
Accelerates at a steady rate over time, so, acceleration is a straight line

8. Slowing Down
We have a constant, negative acceleration, so we use a downward straight line!

9. Limits of Speed-Time Graphs
Can’t show direction
Show only the relationship between speed and time
there are also changes in velocity due to changes in the object’s direction

10. Acceleration Practice in Book
Pg #’s 1-8