1. How fast we move and in what direction are we going.
Speed and Velocity
How fast we move and in what direction are we going.

2. Speed
Speed is a ratio of the distance an object moves to the amount of time it moves
Speed = distance/time
The SI unit for speed is meters/second (m/s)
km/hour is also used

3. Average Speed
It is the total distance traveled divided by the total amount of time it took
Average speed = total distance/total time
The formula is v=Δd/Δt
Δ is the Greek letter delta and it means change

4. Calculating Average Speed
While traveling on vacation, you measure the times and distances traveled. You traveled 35 kilometers in 0.4 hour, followed by 53 kilometers in 0.6 hour. What is your average speed? Use the formula v = total distance/total time
Total distance (d) = 35 km + 53km = 88km
Total Time (t) = 0.4h + 0.6h = 1.0h
v = 88km/1hr = 88km/hr

5. Instantaneous Speed
The rate an object is moving at any given moment in time is instantaneous
the speedometer in a car shows instantaneous speed

6. Graphing Motion Distance and time can be graphed in a line graph
slope = rise/run
In a distance-time graph the slope of the line is the speed
A constant speed will give a diagonal line
When the line is horizontal the car is not moving (stopped)

7. Graphing Motion Constant High Speed
Distance (meters)
Time (seconds)

8. Varying Speed
Distance (meters)
Time (seconds)

9. Velocity
Velocity is the speed and direction an object is moving, it is a vector
A change in velocity is a change in speed, a change in direction or both
When an object is moving at a constant speed and direction it has constant velocity