Session Overview
Covered this week: Balance scales are simple tools that can give the mass of an object relative to another object through finding the equilibrium point. Image courtesy of Lichfield District Council 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 19: Introduction to Mechanical Vibration
 Video Chapters
 Introduction to the single degree of freedom (SDOF) system)
 Finding the equation of motion with respect to the static equilibrium position
 Response of the SDOF system to initial conditions
 Meaning of phase angle in free decay
 Engineers approach to the solution of the 2nd order differential equation with initial conditions
 Estimation of natural frequencies and damping ratios from measured response: the logarithmic decrement
 Video Chapters

Watch Lecture 20: Linear System Modeling a Single Degree of Freedom Oscillator
 Video Chapters
 Concept question discussion of Problem set 9keep
 Damped response of springmassdashpot system to initial conditions
 Finding the response of a pendulum to initial conditions
 Example: Ballistic pendulum
 Experimental determination of damping ratio
 Steady state linear system response to harmonic input
 Demonstration of a beam with a rotating mass shaker
 Video Chapters
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 9: Concept Question Answer Key (PDF)
 Problem Set 9: Problem Solutions and Explanations (PDF)
Looking for something specific in this course? The Resource Index compiles links to most course resources in a single page.