1. Speed and Velocity

2. What is the difference between distance and displacement?
For example, if a trip was recorded on the above line… Let’s say that a person walked 5 paces from the left end and rested for several minutes. Then they continued to travel in the same direction for more 10 paces before turning 180 degrees and walking 8 paces. How far from their origin are they?

3. Speed vs. Velocity Speed = distance/time
Velocity = distance/time in a given direction
For physics, distance=meters, time=seconds unless otherwise noted

4. Instantaneous speed or velocity is determined by calculating the slope of a graphed trip at a specific point OR using a speedometer and compass
Average speed is more commonly used! Average speed=total distance/total time

5. Example1:
Your Best friend lives 4 miles away. Your thinking green so you ride your bike to their house. If it takes 10 minutes to get there, what is your average speed in mi/min? what is your average speed in m/sec?

6. Example 2:
A cheetah can maintain a speed of 25m/s. At this rate, how far will the cheetah run in 10 seconds? In one minute?

7. Velocity Again… Velocity is speed with direction!!
Change in velocity requires a change in speed (speed up or down), a change in direction (turning a corner), OR BOTH!!

8. Standard Velocity Graph
Distance (m)
Time (sec)
Remember because velocity watches a trend/change of one object, we connect our data with a line.

9. Create a velocity graph for the following story problem:
A walker starting from rest travels 10 meters to the right from time 0 to 3 seconds. They then travel another 30 meters to the right in the next 3 seconds.

10. On the same graph:
A second walker starting from rest travels 15 meters to the right from time 0 to 4 seconds. Then turns and walks 25 meters to the left in the next 5 seconds.

11. Homework:
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