Session Overview
Covered this week: The principles presented this week explain why the passengers on this swing ride feel an upward lift as the central structure whirls. Image courtesy of Hillbraith on Flickr. 
Assignments
Problems and Concept Questions
Each problem set has concept questions paired with most problems. Answers to the concept questions are handed in before the overall problem set is due. You should therefore answer the concept questions in each problem set while watching the video lectures for the week. Then, use the Concept Question Answer Key (below in the Check Yourself section) to check your work before continuing to work on the problem set.
Please note that if your answer to the concept question is incorrect, it is likely that you may start down an unproductive pathway to a solution. Try to fully understand the answer to the concept question before you begin the regular problem.
Videos
Lecture Videos

Watch Lecture 5: Impulse, Torque, and Angular Momentum for a System of Particles

Video Chapters

Watch Lecture 6: Torque and the Time Rate of Change of Angular Momentum
 Video Chapters
 Intro to the time rate of change of linear and angular momentum for a particlecoordinates
 Example 1: Rotating mass on a string; dP/dt = tension
 Example 2aPulling the string from a rotating mass through a hole at the axis of rotation. Conservation of angular momentum, h
 Example 2bwork done equals the change in kinetic energy
 Example 3b: Computing external and internal structural torques using dh / dt; angular momentum vector not aligned with the axis of rotation
 Question and answer session
 Video Chapters
Recitation Video and Notes
 Watch Recitation 3: Motion in Moving Reference Frames
 This recitation includes a concept review for the week and covers a problem on velocity and acceleration of a point in a plane using polar coordinates.
 Recitation 3 Notes: V and A of a Point in a Moving Frame (PDF  1.6MB)
 These recitation notes were compiled by Prof. David Gossard, another instructor for the course. His notes go over concepts and problems covered during the recitation sections he taught, and may not precisely correspond to the content covered in the above recitation video.

Check Yourself
Concept Question Answer Key and Problem Set Solutions
The solutions are presented in two files, one with the answers to the concept questions, and one with solutions and indepth explanations for the problems. Work the problems on your own and check your answers when you’re done.
 Problem Set 3: Concept Question Answer Key (PDF)
 Problem Set 3: Problem Solutions and Explanations (PDF  1.1MB)
Looking for something specific in this course? The Resource Index compiles links to most course resources in a single page.