1. QUALITATIVE QUANTITATIVE Physical Situation Mathematical (Formal) Solution RepresentationInterpretation Visual Representaton Symbolic Notation Select Physical Principles/Approach Build Relationships Solve Check Limiting Cases Check Reasonableness Insert Numbers (Experience) (Ideas) Check Dimensions Conceptual and Narrative Representation Solution Statement Problem Solving Model: Revisited

2. QUALITATIVE QUANTITATIVE Physical Situation Mathematical (Formal) Solution RepresentationInterpretation Motion Graphs: origin, signs, units Symbolic Notation General Equations: Kinematics Toolbox Apply Specifics to Build Relationships Solve Check Limiting Cases Check Reasonableness Insert Numbers (Experience) (Ideas) Check Dimensions Assumptions and Approximations: frictionless, constant a, etc. Solution Statement Problem Solving Model: Kinematics

3. QUALITATIVE QUANTITATIVE Physical Situation Mathematical (Formal) Solution RepresentationInterpretation Simply Free Body Diagrams, Vector Drawings, Coordinate Systems, Signs, Axes Symbolic Notation Newton’s Laws for each direction, for each Object Build Relationships Solve Check Limiting Cases Check Reasonableness Insert Numbers (Experience) (Ideas) Check Dimensions Friction, Constant Forces, What to Ignore Solution Statement Problem Solving Model: Newtonian Forces

4. Ch6 Work-Kinetic Energy What is work? – Work changes the energy of a system. Simple Examples: Pushing a box across a floor Catching a box across a floor Carrying a box across a floor Carryingabox Raising a box off a floor Lowering a box on to a floor Pushing a box up a ramp Pulling a box with a rope from above Friction

5. Work More Sophisticated Examples: A block pushed on right and left by A and B Two blocks attached by a spring pushed inward a distance d A block attached to a spring pushing off a wall Work along a curved path Springs, calculus Ch6

6. Key Points about Work Work can be done “on” or “by” objects via forces The sign of the work does not depend on the coordinate system The displacement in the work is based on the point where the force is applied The net work is not necessarily derived from the net force Work-Kinetic Energy Theorem A different perspective Derivation Limitations Revisit previous examples Ch6

7. Lab 4

8. Mid-Semester Deep Breath Lets revisit some advice… “If you knew everything about my shirt, would you know everything about everything?” – Are we studying principles or problems? “Your beliefs and expectations will affect the outcome of your problem solving and the outcome of this course!” – How do you prioritize your time? “Science is any human process relating concepts and experience in a way that is systematic, unambiguous, and communicable order to understand the universe.” – How well are we communicating? How systematic are we being? How are we managing ambiguity? “Math doesn’t mean anything until you give it an interpretation.” – In general do you spend more time thinking about numbers or situations? “The aim of science is insight, not truth.” – Can you distinguish these? “Failure moves us forward.” – How have you dealt with setbacks? “A major role of science is to form and use stories or models that help us understand experience” – Do we practice telling them or dismiss them? Solution Physical Situation Representation: Use words, pictures, mathematics Interpretation