For Quiz 01 Week 1 Videos 1 What is the primary task of an engineer Engineering is the professional art requiring the judgment necessary to adapt knowledge to practical purposes the imagination to conceive original solutions to problems and the ability to predict performance and cost of new devices or processes 2 What is societal role of Engineering Mechanics What does it enable you to do that is valuable to society Structural safety 3 What is meant by Factor of Safety or safety factor Why should it be greater than 1 Safety Factor supply demand The safety factor needs to be greater than 1 to allow for uncertainty in the design process such as calculations strength of materials duty and quality 4 What are the five major steps in structural analysis 1 Isolate Idealize and Draw FBD judgment 2 Pictorial to vectorial Math Physics basic math and physics equations of motion and equilibrium 3 Analyze and augment with empirical laws Judgment 4 Combine and calculate math 5 Check and conclude decide 5 Why do we need to convert a real world situation into a symbolic representation Mathematical reasoning to justify decisions mathematical reasoning that everyone around the world understands and recognizes 6 What is a free body diagram Simplified representation of the system Free body diagrams are diagrams used to show the relative magnitude and direction of all forces acting upon an object in a given situation 7 What are the two kinds of forces that are included in a free body diagram give examples of each 2 Type text External Forces Body force gravity EX Body A is touching body B 8 What is the difference between a motive force and a constraint or reaction force Motive Force Cause acceleration known at FBD drawing time Constraint or reaction forces prevent relative motion unknown at FBD motion 9 What motion is allowed for each of the following 2 D joints Welded Joint Pin Joint Roller or rocker Joint Welded no motion Pin joint roll in place Roller joint heave and sway Rocker joint fixed joint normal force 10 What force or moment s are zero for each of these 2 D joints Welded Pin Roller 11 Do we include internal forces in a FBD No