PHYS 1111 - Introductory Physics I
Chapter 9 - Linear Momentum and Collisions

Study Assignment:

Chapter 9, Sections 9.1 - 9.7

Lesson notes:

The second major conservation law of mechanics will be introduced in this chapter. In combination with the law of conservation of energy, conservation of linear momentum allows the analysis of interactions between objects ranging in size from elementary particles to galaxies. We will apply the law of conservation of linear momentum to the problem of collisions in two-dimensions.

Objectives:

1. Understand the relationship between impulse and momentum, and be able to calculate the magnitudes of forces that occur in collisions.

2. Understand that conservation of linear momentum is a consequence of the application of Newton's Second and Third laws to a system of particles.

3. Be able to apply the principle of conservation of linear momentum to collisions.

4. Be able to write and apply the law of conservation of linear momentum in component form in collision problems.

5. Be able to solve collision problems involving glancing collisions in two-dimensions.

Vocabulary:

impulse
time-average force
linear momentum
elastic collision
inelastic collision
perfectly inelastic collision
ballistic pendulum
glancing collision
center of mass

Sample Problems:

TQ:  9.2
TE:  9.5
TP:  9.3, 9.9, 9.11 , 9.23, 9.27, 9.31

Additional materials:

High-speed video of a baseball striking a flat plate at about 120 mph, taken at 30,000 frames/s, from the Baseball Research Center at the University of Massachusetts-Lowell.

An animation that shows elastic and perfectly inelastic collisions is provided by the University of Toronto.

Another similar animation that allows you to vary mass, velocity and type of collision is provided by Walter Fendt.

Animal collision - from Metacafe.

An inelastic collision between two trains in 1913 provided by Metacafe.

Surendranath Reddy provides an applet demonstrating the motion of the center of mass of an extended object.

Additional resources are available from the text Web site.

Last update: October 09, 2008