1. Describing motion with graphs
Physical science

2. You can use graphs to determine the velocity of an object

3. Constant rightward (+) velocity- 10m/s

4. Car is moving with a changing rightward velocity

5. Motion with changing positive velocity will result in a line of changing positive slope

6. Whatever characteristics the velocity has the slope (line) will exhibit the same characteristics
If it’s a straight line = constant speed
If it’s a curved line = acceleration by speeding up or slowing down
If line starts at zero= the object is starting at the F.O.R.
If the line does not start at zero= the object is either:
-starting near the F.O.R and going away or towards F.O.R.
-starting far from the F.O.R. and going away or towards F.O.R.

7. What can we say about the motion of these two graphs?

8. The graph below represents a negative velocity

9. Check your understanding: use the slope to determine the motion of the objects

10. X t B A C A … Starts at home (origin) and goes forward slowly
B … Not moving (position remains constant as time progresses)
C … Turns around and goes in the other direction quickly, passing up home

11. Different Velocity-time graphs

12. E. Graphing Motion slope = speed steeper slope = straight line =*
E. Graphing Motion
07/16/96
Distance-Time Graph A B
slope =
steeper slope =
straight line =
flat line =
speed
faster speed
constant speed
no motion *

13. E. Graphing Motion Who started out faster? A (steeper slope)
Distance-Time Graph A B
Who started out faster?
A (steeper slope)
Who had a constant speed? A
Describe B from min.
B stopped moving
Find their average speeds.
A = (2400m)/(30min)
A = 80 m/min
B = (1200m) /(30min)
B = 40 m/min

14. None of the graphs below.
Which of the following distance-time graphs shows a person moving closer to a reference point?
Graph 1
Graph 2
Graph 3
None of the graphs below. 1 2 3
d (m)
Time (s)
Time (s)
Time (s)

15. Which of the following shows a person moving at a constant rate?
Graph 1 only.
Graph 2 only.
Graph 3 only.
Graphs 1 & 2.
Graphs 1, 2, and 3. 1 2 3
d (m)
Time (s)
Time (s)
Time (s)

16. Graph 1 Graph 2 Graph 3 None of the above.
Which of the following shows a person moving the fastest away from the reference point?
Graph 1
Graph 2
Graph 3
None of the above. 2 3 1
d (m)
Time (s)
Time (s)
Time (s)

17. A straight horizontal line A slanted line moving up and to the right.
How would a position-time graph appear for an object at that is not moving?
A straight horizontal line
A slanted line moving up and to the right.
A curved line curving up and to the right.
A slanted line moving down and to the left.