This document defines key terms related to speed, distance, and time. It includes examples comparing the constant versus average speed of objects. Constant speed is speed that does not change over time, while average speed is calculated by dividing total distance by total time. The document also contains sample speed and distance vs. time graphs and worksheets for calculating speed from the graphs.

1. Constant Versus Average Speed

2. Ant #1 crawled 12 inches
in 1 second.
Ant #2 crawled 24 inches
in 1 second.
Compare the speed of the ants- which one
is faster? How does the distance compare?

3. DIRECTLY PROPORTIONAL
TO DISTANCE
Greater speed (faster)= more distance
Less speed (slower) = less distance

4. The top plane flew 220
meters in 1 second.
A bottom plane flew
220 meters in 2 seconds.
Compare their speeds-which plane
is faster? How do the times compare?

5. SPEED IS….
Inversely Proportional to
TIME
Greater speed, less time
Less speed, more time

6. CONSTANT SPEED
SPEED
THAT
DOES
NOT
CHANGE

7. CONSTANT
SPEED

8. AVERAGE SPEED
AVERAGE = total distance traveled
SPEED total time

9. AVERAGE SPEED

10. AVERAGE SPEED

11. A car travels 32 km during the first
2 hours. Then it travels 13 km in
the next hour. What is the average
speed of the car?
ANSWER: Avg speed= total distance/total time
total distance = 32 km + 13 km = 45 km
total time = 2 h + 1h = 3 hr
Avg speed = 45 km/3 hr
Avg speed = 15 km/hr

12. CONSTANT SPEED

13. Definitions:
A change in position in a certain amount of time is __________.
__________________ is the rate at which an object moves and is
determined by dividing ____________ by _____________.
_________________________ is speed that does not change.
_________________________ is calculated by dividing the total
distance by the total time.

15. SPEED
WORKSHEET
Complete for homework

16. Ken goes for a walk
0
1
2
3
4
5
6
7
8
9
10
20 40 60 80 100 120
Time (minutes)
Distance(km)
1.Calculate the speed at each point on the y-axis
Time (min) 20 40 60 80 100 120
Distance
(km)
Speed
(km/min)
2. Describe the motion
shown in the graph:
3.Calculate the average
speed for the graph –
how does this value
compare to your
calculations above?
3. How far would Ken
travel if he walked for
another hour (60
minutes)?

17. Ken goes for a walk
0
1
2
3
4
5
6
7
8
9
10
20 40 60 80 100 120
Time (minutes)
Distance(km)
1.Calculate the speed at each point on the y-axis
Time (min) 20 40 60 80 100 120
Distance
(km)
1.5 3 4.5 6 7.5 9
Speed
(km/min)
0.075 0.075 0.075 0.075 0.075 0.075
2. Describe the motion
shown in the graph:
3.Calculate the average
speed for the graph –
how does this value
compare to your
calculations above?
0.075 km/min
3. How far would Ken
travel if he walked for
another hour (60
minutes)? 13.5 km

18. Michelle Goes on a Bike Ride
0
10
20
30
40
50
60
70
80
1 2 3 4 5 6
Time (hours)
Distance(km)
5.Describe the motion shown in the
graph
6.How many different rates are shown?
Label them using A, B, . . . . .
Time
(hours)
A B C D
Distance
(km)
Speed
(min/km)
8. What is the average speed for the entire trip? How does the value compare
to your calculations above?
9. Can you predict how far Michelle will travel if she travels for another 2
hours? Why or why not? What additional information do you need?
7. Calculate the speeds for the different segments of the journey (Hint - you will have to use change in distance!)

19. Michelle Goes on a Bike Ride
0
10
20
30
40
50
60
70
80
1 2 3 4 5 6
Time (hours)
Distance(km)
5.Describe the motion shown in the
graph (moving at varying speed)
6.How many different rates are shown?
Label them using A, B, . . . . .
Time (hours) A (1 h) B (1h) C (2 h) D (1h)
Distance (km)
10 0 40 10
Speed (km/h)
10 0 20 10
8. What is the average speed for the entire trip? How does the value compare
to your calculations above? 11.7 or 12 km/h
9. Can you predict how far Michelle will travel if she travels for another 2
hours? Why or why not? What additional information do you need?
7. Calculate the speeds for the different segments of the journey (Hint - you will have to use change in distance!)