1. Do Now 1. Put these objects in order from slowest to fastest:
Peregrine falcon
Cheetah
Ms. Lusk
Car (at the highway speed limit)
Mako shark
Ocean wave
Maglev train

2. Do Now Answers Put these objects in order from slowest to fastest:
Peregrine falcon (#6, 200 mph)
Cheetah (#5, 70 mph)
Ms. Lusk (#7, 351 mph: JK #2, 28 mph)
Car (at the highway speed limit) (#4, 60 mph)
Mako shark (#3, 31 mph)
Ocean wave (#1, 4.5 mph)
Maglev train (#7, 350 mph)

3. Announcements Quiz over motion, speed, and velocity on Monday.
Lab tomorrow
Parent Lab Night: A week from today
If you need another invitation, please see Ms.Lusk
PLEASE come. It’ll be fun 

4. Speed, Distance, and Time

5. What is speed?
Speed is a measure of how fast something moves or the distance it moves, in a given amount of time.

6. How do we calculate speed?
To calculate speed, we have to use a formula.
Speed=Distance divided by Time

7. Formulas Speed speed = distance time s = d t
*speed of a car is mph = miles = distance
hour time

8. Speed Triangle
To help us solve speed problems, we can use a speed triangle like the one below. D S T ÷ x

9. How do we use this? Step 1: Draw a triangle on your paper.
Step 2: Write in the numbers that you know from the problem.
MAKE SURE THEY ARE IN THE CORRECT PLACE!
Step 3: Use your finger to cover the section of the triangle that you are solving.
If one number is on top of the other, divide.
If two numbers are next to each other, multiply.

10. 4. Distance = 10 meters Time = 1 sec. Speed = S÷ x S

11. What other formulas can we make from our speed formula?

12. Distance Formula
Distance s = d t d = s x t
x t
x t

13. Formulas
Time d = s x t t = d s
÷ s
÷ s

14. Checking for Understanding
What is speed?
What is the formula for calculating speed?

15. Example #1
Ex1: A football field is about 100 m long. If it takes a person 20 seconds to run its length, how fast were they running?

16. Steps to solving equation
100 m
20 s ÷ x
Step one: Identify your distance and your time.
D= 100 m
T= 20 sec
Step two: Place numbers into the triangle.
Step three: Solve for distance. S

17. Solve in your notebook
Ex 2: If you drive at 100 km/hr for 6 hours, how far will you go?
100 km/hr
6 hours ÷ x D
100 km/hr * 6 hours= 600 km

18. Example #3 ÷ T x 3900 km 100 km/hr 3900 km ÷ 100 km/hr= 39 hours
Every summer I drive to Michigan. It is 3900 km to get there. If I average 100 km/hr, how much time will I spend driving?
100 km/hr T ÷ x
3900 km
3900 km ÷ 100 km/hr= 39 hours

19. Example #4
Ex4: If you run at 12 m/s for 15 minutes, how far will you go?

20. Average Speed Speed is not constant. Ms.Lusk and a half marathon
To calculate average speed find the distance traveled, and then divide by the sum of the times.

21. Example #5
An excellent middle school runner might have the following times for the four laps of the 1600-meter race: 83 seconds, 81 seconds, 79 seconds, and 77 seconds.
Step One: Identify the distance traveled.
D=16oo m
Step Two: Add up the seconds it took to complete.
T= 320 sec
Step Three: Place into equation
S = 1600 m
320 sec
Step four: Solve equation
5.0 m/sec

22. On your own
A ball is thrown a total of 18 meters in 3 seconds. What is the average speed of the ball?