1. Motion

2. Warm up day 20 (do this on page 20 of notebook)
speed=distance
time
1. How fast are you going if you cover 13meters in 4seconds?
2. How far will you go if you travel at a speed of 6meters/second for 0.75seconds
3. How long will it take you to travel 5meters at a speed of 3meters per second?

3. Speed a measure of how fast something moves,
the distance it moves, in a given amount of time
Formula:
in physics, we use the units of meters/second
Speed = distance
time
00:00. 4 5 3 1 2 6
What is the ball’s speed?
6 meters

4. Interesting Speeds meters/second miles/hour Cockroach Kangaroo Cheetah
1.25
2.8
Kangaroo 15 34
Cheetah 27 60
Sound
(in 200C air)
343
767
Space Shuttle
(getting into orbit)
7,823
17,500
Light
300,000,000
671,080,888

5. Practice Problems - Speed
If you walk for 1.5 hours and travel 7.5 km, what is your average speed?
2. Calculate the speed of a bee that flies 22 meters in 2 seconds.
S = d t
7.5 km
5 km hr
S = =
1.5 hr
22 m
11 m
sec
S = d t
S = =
2 sec

6. On page 21 write down the following title
Graphical Representation of Motion
Motion can be described using graphs
Distance/time graphs

7. Distance-Time Graph Shows how speed relates to distance and time D50 40 30 20 10 60 70 80 90
100
Time (seconds)
120
Distance (meters) D
This distance-time graph will show a student’s speed as s/he returns to class after lunch.
What is the speed from C-D ?
What is the speed from B-C ? B C
What is the student’s average speed?
What is the speed from A-B ? A

8. Follow along and write down examples from the board

9. Describe What’s Happening (distance-time graphs)
Constant speed; away from starting point
Constant speed; no movement
Constant speed; toward the starting point

10. Complete the speed problems on your own
See Handout.
Add this to problem list:
A student walks 5 meters down the hall in 4 seconds. The student then stops for 4 seconds. Then student then returns to where she started in 4seconds. Draw a distance/time graph that shows this motion.