1. Science Starter (Write the question & Solve in Notebook)
If Torran drives at 68 mph for 5 hours, how far did she travel?
Mrs. Davis is taking a trip to Washington state over the summer break. If she travels at 70 mph for 24 hours, would she make it to WA? Why or why not? (p.s. How far do you think Washington is? Think critically!!!)

2. Velocity and Acceleration
Speed it up!

3. Velocity: What is it? Velocity is a speed in a specific direction.
Formula: v= d/t + direction
Examples of velocities:
30 m/s to the left
45 mi/hr west
18 km/s up

4. Velocity Example Problems
Tim was taking a rocket ship to his home in outerspace. If the rocket travels 900 km in 2 minutes towards the sun, what is his velocity?
Faith is driving North to her grandparents’ home in Ohio. If she drives 720 km for 12 hours, what is her velocity?

5. REMEMBER!!!!!!!
Solve Velocity problems JUST LIKE SPEED problems. Just add in a DIRECTION.

6. Speed and Velocity….

7. Acceleration
Acceleration is a change in velocity over time

8. Check for Understanding
What two components make up velocity?

9. Check for Understanding
Velocity
Speed
Direction

10. Acceleration Def.: Change in _________ over ___________
Can be change in speed or direction
(speed up, slow down, or change direction)

11. Acceleration Def.: Change in _velocity_ over __time____
Can be change in speed or direction
(speed up, slow down, or change direction)

12. Check for Understanding
Is this ball accelerating?
Yes! Because the direction is changing.

13. Which cars are accelerating?B C
Cars B and C!

14. Acceleration
Acceleration is not just a change in velocity, it’s how fast that change happens.

15. Which car has the greatest acceleration?B C
Car C!

16. Discovery Education Video

17. Acceleration
To measure it, you must know the initial velocity, the final velocity, and the time it takes to make the change.

18. Acceleration Acceleration = ∆v/ t Def.: Change in velocity
Can be change in speed or direction
(speed up, slow down, or change direction)
Acceleration = ∆v/ t

19. Acceleration
Initial Velocity –Object’s velocity when you start measuring acceleration.
Final Velocity –Object’s velocity when you finish measuring acceleration.
 - Greek letter delta – “change”

20. Acceleration = change in velocity time
The unit for acceleration is m/s2.  v a = t

21. Acceleration
v is the difference between the final velocity (vf) and the initial velocity (vi).
v = vf - vi

22. Acceleration Acceleration = ∆v/ t Def.: Change in velocity
Can be change in speed or direction
(speed up, slow down, or change direction)
Acceleration = ∆v/ t
∆v = vf – vi

23. Example 1
A roller coaster’s velocity at the top of a hill is 10m/s. Two seconds later it reaches the bottom of the hill with a velocity of 26m/s. What is the acceleration of the roller coaster?

24. Answer vf = 26 m/s vi = 10 m/s t = 2 s Acceleration = ∆v/ t
a = 26m/s – 10m/s
2 s
a = 16m/s 2s
a = 8m/s/s or 8m/s2

25. Examples 2-4 – Try them!
2. A car travels at 60 miles per hour around a curve. Is the car accelerating?
3. A car travels in a straight line at 60 mi/hr. Is the car accelerating?
4. A car goes from 0 mph to 60 mph in 6 seconds. What’s the car’s acceleration?

26. Answers:
1. Yes! Because it’s changing direction. 2. No! It’s not changing speed or direction. 3. -vf = 60 mph vi = 0 mph t = 6 s -a = vf – vi t -a = 60 – 0 mph = 10 m/s2 6 s

27. Graphing Velocity vs. Time
Constant acc.
No acc.
Increasing acc.

28. Exit Ticket What is the unit of acceleration? Solve these problems:
A car is traveling at a velocity of 24 km/hr west and increases to a speed of 50 km/hr west in 4 seconds. What is the car’s acceleration?
Michelle is walking to the store at a velocity of 5 km/hr. She realizes that the store is closing in a few minutes. She accelerates to running at a rate of 15 km/hour in 2 seconds. What is her rate of acceleration?