© 2010 Pearson Education, Inc. Week 4 Day 2: Topics Slide 1-7 Particle Model Motion Diagrams Adding and Subtracting Vectors Graphically Delta v diagrams

© 2010 Pearson Education, Inc. A graph of velocity versus time for a hockey puck shot into a goal appears like so: Which of the following position graphs matches the above velocity graph? Checking Understanding A.B.C.D. Slide 2-21

© 2010 Pearson Education, Inc. A graph of velocity versus time for a hockey puck shot into a goal appears like so: Which of the following position graphs matches the above velocity graph? Answer A.B.C.D. Slide 2-22

© 2010 Pearson Education, Inc. Example Problem A car moves along a straight stretch of road. The graph below shows the car’s position as a function of time. At what point (or points) do the following conditions apply? The displacement is zero. The speed is zero. The speed is increasing. The speed is decreasing. Slide 2-14

© 2010 Pearson Education, Inc. Examples of Motion Diagrams 5

© 2010 Pearson Education, Inc. The Particle Model A simplifying model in which we treat the object as if all its mass were concentrated at a single point. This model helps us concentrate on the overall motion of the object. Slide 1-16

© 2010 Pearson Education, Inc. Position and Time The position of an object is located along a coordinate system. At each time t, the object is at some particular position. We are free to choose the origin of time (i.e., when t = 0). Slide 1-17

© 2010 Pearson Education, Inc. Slide 1-7 Which Way? Which way is this object moving? A.LeftB. RightC. Can’t tell Is it speeding up or slowing down? A.Speeding upB. Slowing down C. Can’t tell How can you tell?

© 2010 Pearson Education, Inc. Here is a motion diagram of a car moving along a straight stretch of road: Which of the following velocity-versus-time graphs matches this motion diagram? Checking Understanding A. Slide 2-13 B.C.D.

© 2010 Pearson Education, Inc. Here is a motion diagram of a car moving along a straight stretch of road: Which of the following velocity-versus-time graphs matches this motion diagram? Slide 2-14 C. Answer

© 2010 Pearson Education, Inc. Vectors Slide 3-9

© 2010 Pearson Education, Inc. Adding Vectors Graphically Slide 1-33

© 2010 Pearson Education, Inc. Adding Displacement Vectors Slide 1-31

© 2010 Pearson Education, Inc. Example: Adding Displacement Vectors Jenny runs 1 mi to the northeast, then 1 mi south. Graphically find her net displacement. Slide 1-32

© 2010 Pearson Education, Inc. Slide 1-7 Adding Vectors Find the following resultants graphically

© 2010 Pearson Education, Inc. Vector Subtraction Slide 3-10

© 2010 Pearson Education, Inc. Slide 3-11 Acceleration Vectors