1. “Mu of the Shoe” Friction: Day 2

2. Curriculum Big Idea: All forces arise from the interactions between different objects. Concept: When two surfaces of objects are in contact with each other, the force of friction between them depends on the nature of the materials in contact and the normal force. Competency: Construct a free body diagram indicating the magnitude and direction of the forces on an object and use information from the diagram to determine the motion of the object. PA Standard 3.2.10.B1: Analyze the relationships among the net force acting on a body, the mass of the body, and the resulting acceleration using Newton’s Second Law of Motion.

3. Today’s Agenda - Academic Opener – What is friction? Go over your reflection responses (homework). Define Physics Words. (in the packet) Free Body Diagrams and friction Closure: Say one thing that you have learned in the two lessons on friction.

4. Honors Goals Design an experiment and conduct an experiment to compare the amount of friction between different surfaces. Solve real world problems with friction using Newton’s Second Law: Fnet = m×a

5. Today’s Agenda - Honors Opener – Read the Furniture Company Scenario and your Materials List as a class. Individually, write down your ideas to solve the problem. Discuss your ideas in small groups and as a class. As a class, design an experiment to determine the coefficients of friction between the three available surfaces and the lab tables. Go over friction problems (homework). Define the Physics Words, and answer the reflection questions. (see packet) Closure: Say one thing that you have learned in the two lessons on friction. Take Home Assignment: Complete the friction scenario handout

6. Scenario A new furniture company in Haverford Township is asking for your help in determining the best of three materials to use on the bottom of their dining room chairs. The company wants the chairs to have the least possible amount of friction when slid across a dining room floor. The dining room floor surface is the same as your lab table surface.

7. Materials for Each Group 1 felt pasco slider 1 cork pasco slider 1 plastic pasco slider 1 spring scales a set of masses clean lab tables friction scenarios and free body diagram handouts

8. Physics Words Force of Friction: a force that slows objects down Normal Force: Force of a surface on an object. Always perpendicular to the surface Force to Slide: Force required to slide the object at a constant speed (equal to the force of friction). Weight: Force of gravity on an object