1. Did you know More than ten people a year are killed by vending machines. Weds. 9/2 2 nd period: We are doing a lab today Quiz changed to Tuesday

2. Did you know More than ten people a year are killed by vending machines. Weds. 9/2 IF your paper has a “CSM” at the top – that means come see me – after our notes today I will call those with CSM on their papers to the back together to make sure we clear up any misconceptions. CHANGE IN PLANS: Quiz Tuesday

4. Review of yesterday Distance and Displacement – answers can be added to the bottom of your notes from yesterday 1. A softball player leaves the batter’s box, overruns first base by 3.0 m and then returns to first base. Compared to the total distance traveled by the player, the magnitude of the players total displacement from the batter box is smaller / larger / the same? 2. Hannah leaves a history classroom and walks 10 m north to a drinking fountain. Then she turns and walks 30 m south to an art classroom. What is Hannah’s total displacement from the history classroom to the art classroom?

5. You can describe the motion of an object by its position, speed, direction, and acceleration. 80 mph Speed and Velocity

8. The car below is traveling at a constant speed of 100 mph. Is the car’s velocity the same?

9. IF YOU CAN’T SAY IT – YOU DON’T KNOW IT! Write a brief summary at the bottom of your notes – compare and contrast speed and velocity. Make sure you include the terms: distance, displacement, vector and scalar.

10. The speedometer of a car moving northward reads 60 km/h. It passes another car that travels southward at 60 km/h. Do both cars have the same speed? Do they have the same velocity? PRACTICE PROBLEM 1 Answer: Both cars have the same speed, but they have opposite velocities because they are moving in opposite directions.

11. You walk 10 meters East in 2 minutes. What is your speed? What is your velocity? PRACTICE PROBLEM 5

12. FIRST STEP IN SOLVING PHYSICS PROBLEMS… MAKE SURE ALL OF YOUR UNITS MATCH. A dolphin swims 15 km/hr. How far will it travel in 5 minutes? 25 seconds? PRACTICE PROBLEM 3

13. You drive a car 2 hours at 40 km/h, then 2 hours at 60 km/h. What is your average velocity? Do you get the same answer if you drive 100 km at each of these two speeds? Answer: 50 km/h no, 48 km/h PRACTICE PROBLEM 2

14. Mrs. Rice travels 15 meters at a rate of 10 m/s south. She then travels 100 meters north at a rate of 15 m/s. What is her average speed? What is her average velocity? PRACTICE PROBLEM 4

17. Types of Speed Types of SpeedDescription Example INSTANTANEOUSSpeed at any given Your point in time speedometer AVERAGETotal distance divided Road Trip by total time. CONSTANTSpeed that does not cruise change control

18. Velocity vs. speed Speed is a scalar quantity. It is how fast you are traveling. When you look at the speedometer on your car, it tells you the speed you are traveling at that moment. Velocity is a vector quantity. It is how fast you are going and in what direction. If you are traveling to Dallas, you may be traveling at 70 mi/hr, North. http://www.thinglink.com/scene/385974212231168000

19. Tutorial Links http://www.problemsphysics.com/mechanics/motion/velo _spe_tutorials.html