1. September 29, 1998 Comments about the test
Can’t discuss actual problems yet except by
I can view your answers and give credit
Gave same test to my P5 class... They had
1 1/2 hrs, half closed-book… one H.S.
student got 95.
What is on WEB… schedule, exploratories

2. September 29, 1998 2 Laws of Falling Bodies… Aristotle vs Galileo
coffee filters, films, interactive physics
Patterns on earth and moon
When is a body “freely falling”?
The basic concepts of kinematics…
Position relative to reference frame (x)
Velocity… Acceleration...

3. September 29, 1998 3 Position… shown every second.
Position (m)
(m) P O S I T N 12 10 8 6 4 2
Time (s)

4. September 29, 1998 4 Velocity measures the change in Position
during a change in time
VELOCITY = Change in Position
Change in Time
Go back to graph to see velocity on a
Position-time graph ….. SLOPE

5. September 29, 1998 5 Computing the average velocity of a trip
Each group will compute result…
A driver drove for 2 1/2 hours at 60 miles
per hour, stopped for 1 hour, then drove at
40 miles/hour for 1 hour, stopped for 15
minutes, then went 60 miles in 75 minutes.
What is the average velocity for the trip?

6. September 29, 1998 6 Putting the trip on a graph
Velocity as a function of time….
Position as a function of time…
When the velocity changes… we have
ACCELERATION
ACCELERATION = change in velocity m/s
change in time s

7. September 29, 1998 7 Observing Accelerations (Interactive Physics)
Falling Objects (a look at V, A)
Inclined Planes
Pendulum
Ellipse
Parabola (Projectile Motion)
Highway
Roller Coaster