1. Uniform motion
TPS what is uniform motion

2. Objects in uniform motion travel equal displacements in equal time intervals.
The position of the ball in this photo is shown at equal time intervals
Objects in uniform motion do not speed up, slow down, or change direction.

3. Graphing Uniform Motion
Motion of an object can be analyzed by drawing a position-time graph.
Uniform motion is represented by a STRAIGHT LINE on a position-time graph

4. A position-time graph plots
POSITION on the vertical axis
(y axis)
TIME on the horizontal axis
(x axis).
A BEST-FIT LINE is a straight line that most closely fits the points.

5. Is the motion uniform?

6. Slope
The slope of a graph refers to angle, or steepness, of the line connecting the data points
To calculate slope we divide
Slope= rise = y2 – y1
run x2- x1

8. Positive Slope
Motion in the POSITIVE direction (usually RIGHT,EAST,UP) is represented by a line that slants up to the right.
Calculate the slope:
20cm/s

9. ZERO SLOPE A horizontal line indicates that the object is STATIONARY
Calculate Slope:

10. NEGATIVE SLOPE
Motion in the negative DIRECTION is indicated by a line that slants down to the right.
Calculate Slope:
Negative 0.5 m/0.2s = -2.5m/s

11. Describe the motion for each of the time intervals a) 0 s – 6 s
b) 6 s – 10 s
c) 10 s – 12 s
d) 12 s – 16 s
e) 16 s – 18 s
f) 18 s – 20 s
2m/6sec =
0/4sec =
4m/2sec =
0-6m/4 sec =
18-16 m/2 s
-2 -0m/2s = -1 m/s

12. In class activity p355

13. Describe the motion for each of the time intervals a) 0 s – 6 s
b) 6 s – 10 s
c) 10 s – 12 s
d) 12 s – 16 s
e) 16 s – 18 s
f) 18 s – 20 s
2m/6sec =
0/4sec =
4m/2sec =
0-6m/4 sec =
18-16 m/2 s
-2 -0m/2s = -1 m/s

14. Homework
8-1C p352