1. 1.2 Speed and Velocity

2. Speed
Speed is a scalar quantity that measures distance over time. There are 3 types of speed:
Instantaneous Speed: The speed of an object at a particular moment in time
Example: Speed measured by a radar gun
Constant Speed: Occurs when the instantanous speed remains constant over a period of time
Example: Using cruise control

3. Speed
Average Speed: The total distance travelled divided by the total time elapsed for a trip
Equation:
Where: Δd = distance travelled
Δt = elapsed time

4. Examples
Sally rides her bike to school. It is a distance of 8.0 km. If it takes her 15 minutes, calculate her average speed (in km/h).
Fred can roller blade at a speed of 11.5 km/h. If it is 4.5 km to his friend’s house, how long will it take him to get there in minutes?

5. Velocity
Velocity is a vector quantity that measures the change in position over time. There are three types of velocity:
Constant velocity: occurs when traveling at a constant speed in one direction.

6. Velocity
Average velocity: The resultant displacement divided by the total time elapsed
Where Δd = resultant displacement
Δt = time

7. Examples
It takes John 30 minutes to drive home from work. If his resultant displacement is 26 km [W] what is his average velocity (m/s)? 
The average velocity of a Canadian goose is 2.5 m/s [S]. How long will it take for the goose to travel 5 km [S]?

8. Examples
Anna ran 4 km [E] then 3km [S]. If the entire run took her 45 minutes. 
What was her average speed (km/h)?
What was her average velocity (km/h)?
Why are the two values different?

9. Homework
Questions p. 15 #1-3 p. 18 #1-2 p. 20 #6-8