MECE 102 Engineering Mechanics Lab A First Year Course in Newtonian Mechanics, Experimentation, and Computer Tools Created by the Faculty of the Mechanical Engineering Department in the Kate Gleason College of Engineering at RIT

Week 10 Topics Course Review Exam #2 Discussion Lab Group Peer Evaluation Group Member Evaluations for Weeks Introduction to MATLAB Simulation of Simple Harmonic Motion Logbook Evaluation

Lab Logistics Go to PC Lab (or use any PC) to go through the MATLAB Tutorial videos prior to Studio Remember to Drop-off Logbooks at Start of Exam #2 this Saturday! Logbooks will be returned to your mailfolders Monday of Week 11

Course Review

Exam #2 Information Saturday November 2 nd, 2013 Room  Xerox Auditorium 8:05am – 9:35am  1.5 hours Closed-Book, Closed Notes Bring an approved Calculator 3 Problems 1 – Set of 10 Multiple Choice Problems 2 – Long-Answer HW style problems

FORMULATE: State the Known Information The system being analyzed is the same Spring – Mass Simple Harmonic Motion (SHM) system as Week 9 Given, Unknowns, Basic Equations, Schematic Diagrams, and FBD’s are the same as Week 9 Given the mass, m, of a dead weight suspended from a linear elastic spring. Given the spring constant, K, of the spring, and the initial displacement, z 1, of the mass, m, from the neutral position. Find the transient response of the vertical position, z(t), of the mass, m, as a function of time, t.

FORMULATE: Identify the Desired Information

FORMULATE: Identify Assumptions

Figure 9.1: Schematic Diagram of a mass suspended from a spring with a transducer oriented to measure oscillation. CHART: Schematic Diagram Note the Neutral Position of the spring, with no external mass applied, is different than the Equilibrium Position, z 0, associated with the spring and mass.

Figure 9.2: Free Body Diagrams of a mass and spring, constrained to move in tandem. CHART: Free Body Diagram

EXECUTE: Apply and Simplify the Governing Equations Also recall the initial condition of the mass – spring system: position

EXECUTE: Apply and Simplify the Governing Equations Eqn is not a standard Algebraic equation. Eqn is known as a non-homogenous linear ordinary differential equation. MATLAB will be used to evaluate equation 9.28 and simulate the response of the Spring – Mass system.

EXECUTE: Apply and Simplify the Governing Equations

EXECUTE: Utilize MATLAB program MATLAB has several “sub-windows” as illustrated below:

EXECUTE: Utilize MATLAB program Use the pull down menu to navigate to the “Help - Product Help - Getting Started“ Video. A new window will popup, similar to that shown below.

MATLAB video

Review Problem

a fastball weighs 145[g] What is the speed of the pitch?