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Warm Up. Describe what the V-T graph would look like for an object with negative acceleration when it starts with a.) no velocity b.) positive velocity c.) negative velocity Be sure to describe what will happen as time continues. 0:09. 0:07. 0:06. 0:08. 0:04. 0:05. 4:00. 3:00.
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Warm Up Describe what the V-T graph would look like for an object with negative acceleration when it starts with a.) no velocity b.) positive velocity c.) negative velocity Be sure to describe what will happen as time continues. 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 48-51 • Personal Practice • # 1-4 on page 55
A great graphical picture, but a lot of work to answer small questions.
The 5 Big Kinematic Equations These equations will help us pull the right information from our situation.
How did we get these equations? How do we use these equations? A closer look at each one
Definition of average Acceleration: Now Rearrange!
Example A car can accelerate at a rate of 5 m/s2. How long will it take for the car to reach 80 km/h?
Example A car can accelerate at a rate of 5 m/s2. How long will it take for the car to reach 80 km/h?
Now you try (in groups)! A motorcycle with an initial velocity of 6.0 m/s [E] accelerates at 4.0 m/s2 [E]. How long will it take the motorcycle to reach a final velocity of 36.0 m/s [E]? An elk moving at a velocity of 20 km/h [N] accelerates at 1.5 m/s2 [N] for 9.3 s until it reaches its maximum velocity. Calculate its maximum velocity, in km/h.
& Start with:
& Start with: Put them together!
& Start with: Put them together! And Rearrange!
Now you try (in groups)! A dog running at a velocity of 16 m/s [S] slows down uniformly to a velocity of 4.0 m/s [S] in 4.0 s. What is the displacement of the dog during this time? A ball moves up a hill with an initial velocity of 3.0 m/s. Four seconds later, it is moving down the hill at 9.0 m/s. Find the displacement of the ball from its initial point of release.
Take what we know from the last equation: Rearrange:
Take what we know from the last equation: Rearrange: Expand:
Expand: Use equation #1:
Expand: Use equation #1: To get:
Expand: Use equation #1: To get: Now Expand & Rearrange!
Now you try (in groups)! A skier is moving down a uniform slope with an initial speed of 3.0 m/s. If the acceleration down the hill is 4.0 m/s2, find the skier’s displacement after 5.0 s. A motorcycle is traveling at 100 km/h on a flat road. The rider applies the brakes to slow down the motorcycle at the rate of .80 m/s2 for 30 s. How far did the motorcycle travel during this time?
Group Experiment: Question: What is the acceleration due to gravity? Procedure: Hold a ball 3 meter high and time how long it takes to reach the ground. With this information and using the third equation, find the acceleration that the ball experienced.