ch. 4 projectile motion - siena science · copyright © 2008 pearson education, inc., publishing as...
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Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Ch. 4 Projectile Motion
• Finding the acceleration vector
• Motion in 2 dimensions
• Motion map
• Equations of motion: x, y
• Monkey hunting - starring George Hassel
• Projectile Motion Worksheets
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Acceleration The average acceleration of a moving object is defined as the vector
As an object moves, its velocity vector can change in two possible ways. 1. The magnitude of the velocity can change, indicating a change in speed, or 2. The direction of the velocity can change, indicating that the object has changed direction.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Tactics: Finding the acceleration vector
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Tactics: Finding the acceleration vector
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
EXAMPLE 4.1 Through the valley
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A particle undergoes acceleration while moving from point 1 to point 2. Which of the choices shows the velocity vector as the object moves away from point 2?
QuickCheck 4.1
Slide 4-23
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A particle undergoes acceleration while moving from point 1 to point 2. Which of the choices shows the velocity vector as the object moves away from point 2?
QuickCheck 4.1
Slide 4-24
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Projectile Motion
Projectile motion is made up of two independent motions: uniform motion at constant velocity in the horizontal direction and free-fall motion in the vertical direction. The kinematic equations that describe these two motions are
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
EXAMPLE 4.4 Don’t try this at home!
QUESTION:
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EXAMPLE 4.4 Don’t try this at home!
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A heavy red ball is released from rest 2.0 m above a flat, horizontal surface. At exactly the same instant, a yellow ball with the same mass is fired horizontally at 3.0 m/s. Which ball hits the ground first?
A. The red ball hits first.
B. The yellow ball hits first.
C. They hit at the same time.
QuickCheck 4.5
Slide 4-53
Think-Pair-Share
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A heavy red ball is released from rest 2.0 m above a flat, horizontal surface. At exactly the same instant, a yellow ball with the same mass is fired horizontally at 3.0 m/s. Which ball hits the ground first?
A. The red ball hits first.
B. The yellow ball hits first.
C. They hit at the same time.
QuickCheck 4.5
Slide 4-54
Think-Pair-Share
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A 100 g ball rolls off a table and lands 2.0 m from the base of the table. A 200 g ball rolls off the same table with the same speed. It lands at distance
A. 1.0 m. B. Between 1 m and 2 m. C. 2.0 m. D. Between 2 m and 4 m. E. 4.0 m.
QuickCheck 4.6
Slide 4-55
Think-Pair-Share
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
A 100 g ball rolls off a table and lands 2.0 m from the base of the table. A 200 g ball rolls off the same table with the same speed. It lands at distance
A. 1.0 m. B. Between 1 m and 2 m. C. 2.0 m. D. Between 2 m and 4 m. E. 4.0 m.
QuickCheck 4.6
Slide 4-56
Think-Pair-Share
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Problem-Solving Strategy: Projectile Motion Problems
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Projectile Motion Worksheets
• Do Worksheet 1 & 2 • Group whiteboard and share 1-2 hard ones at
the end • Finish the rest at home; bring on Tuesday!
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Upcoming Assignments
• MasteringPhysics online HW due tonight, Thursday 9/20 by 11 pm
• Read Chapter 4 to the end by Tuesday 9/25 • Pre-class MasteringPhysics assignment due before
class on Tuesday 9/25 • MasteringPhysics online HW due, Thursday 9/27 by
11 pm
• Exam 1 coming up on 10/2