Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley PowerPoint ® Lectures for University Physics, Twelfth Edition – Hugh D. Young and Roger A. Freedman Lectures by James Pazun Chapter 8 Momentum, Impulse, and Collisions
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley How does momentum relate to mass and velocity? Understanding momentum begins with the simple relationship that momentum is equal to mass multiplied by velocity.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Compare momentum and kinetic energy The impulse–momentum relationship depends on duration of an impact while the work-energy theorem focuses on the distance of force application. Refer to Conceptual Example 8.1. Consider Example 8.2, the figure below at right completes that question.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Duration of an impact Figure 8.6 and Figure 8.7 are both image/diagrams related to sports. They are, in fact, of the same duration. The bottom figure assists the setup of Example 8.3. Consider Example 8.3.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Like energy, momentum also has conservation rules Refer to Figure 8.8. No forces are at play save those from the astronauts. Refer to Figure 8.9. Many forces are at work.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Don’t forget that momentum is a vector
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Objects colliding along a straight line Consider the collision in Example 8.5.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Now, consider a two-dimensional collision Considering even just two dimensions makes the problem much more intricate. Consider Example 8.6.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Elastic compared to inelastic
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Completely (or nearly) inelastic collisions Consider Example 8.7 and Figure 8.17 at right below to help you.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley The ballistic pendulum Consider Example 8.8
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley A possible simple model for automobile accidents Refer to Example 8.9.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Elastic collisions—Figure 8.21 Billiard balls are a very good example of objects that collide elastically.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley A two-dimensional elastic collision Consider Example 8.12.
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Many centers of mass
Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Tug-of-war without friction (on the feet) Refer to Example 8.14.