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Warm Up. Which of these graphs is not like the others and why?. 0:09. 0:07. 0:06. 0:08. 0:04. 0:05. 4:00. 3:00. 2:00. 1:00. 0:03. 0:01. 0:02. 5:00. 0:10. Times Up. Bulletin Board. Readings Pages 14-19 Personal Practice # 4-8 on page 13. Speed & velocity.
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Warm Up Which of these graphs is not like the others and why? 0:09 0:07 0:06 0:08 0:04 0:05 4:00 3:00 2:00 1:00 0:03 0:01 0:02 5:00 0:10 Times Up
Bulletin Board • Readings • Pages 14-19 • Personal Practice • # 4-8 on page 13
Speed Distance covered per unit of time.
speed • Distance is a scalar. • \ Speed is a scalar. • What are some examples? • Speedometer on your vehicle. • Shutter speed for a camera. • Speed of light ~3×108 m/s
speed • Distance is a scalar. • \ Speed is a scalar. • What are some examples? • Speedometer on your vehicle. • Shutter speed for a camera. • Speed of light ~3×105 km/s Constant Speed in vacuum
Constant speed Equal increments
Constant speed Uniform Motion
What about non-uniform motion? What is the speed here?
Look at the overall distance. ? Calculate the Average Speed.
Average Speed = = Example: Zachary’s alarm was not set last night & he is in a hurry. He jumps on the bus & travels 12.6 km down Kennedy Rd for 12.0 minutes. He exits the bus at Sheppard Ave & waits 2 minutes & 34 seconds for the next bus to arrive. He then climbs aboard & travels for 15.0 minutes and exits the bus after 16.0 km. Don’t forget that the buses stop at every major street along the way. What is Zachary’s average speed? A = 17.7 m/s B = 16.1 m/s C = 58.0 km/h D = 63.6 km/h
We can use this formula in many different ways: If David drives his vehicle at an average speed of 62 km/h every morning for 24 minutes on his way to school, then what is David’s distance from NTCS ? A = 24.8 km B = 0.043 km C = 1500 m D = 25000 m
Group Questions Cell phone signals travel at an average speed of 300,000 km/s. How long will it take for a friend to get your text if you are in a city 1,350,000 km away? The grade 11 physics class decides to take a trip to Canada’s Wonderland. The bus travels at an average speed of 90 km/h. If the trip takes 27 minutes, how far is Canada’s wonderland from the school?
Group Questions Cell phone signals travel at an average speed of 300,000 km/s. How long will it take for a friend to get your text if you are in a city 1,350,000 km away? The grade 11 physics class decides to take a trip to Canada’s Wonderland. The bus travels at an average speed of 90 km/h. If the trip takes 27 minutes, how far is Canada’s wonderland from the school?
There’s more to the story.... Distance per unit time Speed
There’s more to the story.... Displacement per unit time ?
There’s more to the story.... Displacement per unit time Velocity
There’s more to the story.... Displacement per unit time Velocity Vector same direction as displacement Vector
Average Velocity Average Velocity =
Example: What is the average velocity over the whole 7 seconds? What is the average velocity over the first 3 seconds? What is the average velocity over the last 3 seconds? What is the average velocity over the fourth second?
Example: Notice that the average velocity for uniform motion is the slope of the line on a Position-Time graph.
Example: There are two types of zero average velocity here. Can you spot them?
Example: There are two types of zero average velocity here. Can you spot them?
Group Problem: A train leaves the station and travels forward at a constant velocity of 100 km/hr for 15 minutes. It stops at the station for 2 minutes while passengers board and then continues at its original speed (100 km/hr) for another 20 minutes. What is the average velocity of the entire trip?
Group Problem: A train leaves the station and travels forward at a constant velocity of 100 km/hr for 15 minutes. It stops at the station for 2 minutes while passengers board and then continues at its original speed (100 km/hr) for another 20 minutes. What is the average velocity of the entire trip?