1. Warm-Up
List the steps, in order, for the scientific method (hint: there are 7).
Perform the following calculations and report the results with the correct number of sig figs.
= ________
5. x 2.00 = _______

2. Objective
Identify key differences between speed and velocity.

3. Agenda Interpreting Graphs Game Speed vs Velocity
Practice calculating speed & velocity
Interpreting velocity vs time graphs

4. Speed When in life do you hear people talk about speed?
When have you heard people talk about velocity? Is there a difference? If so, what is it?

5. Kinematics Study of motion – but not what causes the motion
Three terms used in kinematics:
Position
Velocity
Acceleration

6. Physics of Hockey As you watch the video, write down:
The definition for velocity and acceleration
How to calculate velocity and acceleration.

7. Speed vs Velocity What have we learned so far about speed?
What did we just learn about velocity?

8. Recall: Distance vs Displacement
Scalar quantity – independent of direction.
How far an object travels along a path.
Can only be positive
Vector quantity – depends on direction.
Straight-line path from start to finish.
Can be positive or negative.
What does it mean to be negative displacement?

9. Tying this to Speed and Velocity
S = distance/time
Scalar
Can only be positive.
What are the units for speed?
v = displacement/time
Vector
Can be positive and negative.
This indicates the direction.
What does it mean to have negative velocity?
What are the units for velocity?

10. Recall: -5 m/s Can’t be negative Velocity
What was the speed of this graph?
-5 m/s
What did we just learn about speed though?
Can’t be negative
So, did we solve for speed or velocity?
Velocity
Note: the process for solving for speed and velocity is the same – you just have to provide the dir

11. Practice solving for speed and velocity

12. Problem 1:
Find the average speed of a car that goes 80. mi in 3.0 hrs.
mi/hr = 27 mi/hr

13. Problem 2:
If there was an airplane that went 2,175 miles in 3.5 hours. Find the average speed.
= 620 mi/hr

14. Problem 3:
When you combine two velocities that are the same direction you ADD to get the resultant velocity. If a train is going 20. mph east and a passenger is going 2.0 mph east (the same direction). What is the passenger’s resultant velocity?
20. mi/hr mi/hr = 22 mi/hr east

15. Problem 4:
When you combine two velocities that are the opposite direction you SUBTRACT to get the resultant velocity. If a train is going 20 mph east and a passenger is going 2.0 mph west (the opposite direction). What is the passenger’s resultant velocity?
20 mi/hr mi/hr = 18 mi/hr east

16. Partner Practice Find a partner (only 1).
You EACH need your own sheet of paper.
You will answer the questions on the worksheet – this is a Yes/No worksheet again
Meaning, I will only answer Yes/No questions
Pay attention to directions (if given), units (which may need conversion) and significant figures!

17. Graphing Speed vs Time
On the next slide is an image of both a position vs time graph and a speed vs time graph.
In groups of four, you will write down what information you can learn from both graphs.

20. Exit Ticket:
How is speed different from velocity?