1. Unit 1, Lesson 3: Displacement vs. Time Graphs

2. Example 1: Constant Velocities
Find the velocity at
0.5 seconds,
2.0 seconds,
5.0 seconds.
d) Find the average velocity.
a) velocity = slope = 0
b) velocity = slope = (60-20)/(3-1) = 20 m/s
c) v = (20-60)/(6-4.5) = m/s
d) Average v = (total displacement)/(total time) = 0
20 min

3. Example 2: Changing Velocity
A rocket takes off and the height is recorded as shown. a) Find the average velocity of the rocket. b) Find the velocity at 20 and 40 seconds.
h (m)
t (s) 15 10 60 20
135 30
240 40
375 50
540
a) Average velocity = (total displacement)/(total time)
= 540/60
= 9.0 m/s
5 min
b) Find the slope of the tangent at each point…

4. Displacement vs. Time for a Rocket
5 min
At 20s: v = slope of tangent = (120-0)/(30-10) = 6 m/s
At 40s: v = ( )/(48-33) = 12 m/s
Note: These values are approximate!

5. Brain Break!

6. Practice:
Complete the Velocity Graphing Exercise.
25 min

7. Unit 1, Lesson 4: Interpreting Graphs

8. Interpreting Graphs Describe the motion: Object accelerates from rest
5 min
Object accelerates from rest
then decelerates and stops
Object moves backwards
or down and accelerates

9. Sketch a graph of d vs. t for each: 100 m race Bungee jump (2 bounces)
Draw a graph to show an object moving forwards at a constant speed, then slowing down and stopping.
Your turn!
Sketch a graph of d vs. t for each:
100 m race
Bungee jump (2 bounces)
Parachute jump
20 min

10. Brain Break!

11. Try Graphing This!
15 min

12. Practice:
Complete the Velocity Practice worksheet.
15 min