**Static & dynamic friction**

background [prelab assignment (15 points) due at the begining of lab]

1. design experimental protocol and subsequent data analysis to accomplish the goals of the purpose of this lab activity

purpose

determine static coefficient of friction as a function of mass and the nature of the surface

determine kinetic coefficient of friction as a function of mass and the nature of the surface

relate force on object and its mass and its acceleration and its velocity

role of contact area on friction

role of rolling versus non-rolling wheels on friction

materials

motion detector

force sensor

balance

object with different surface / mass

cart

methods / data analysis

student design

based on the Central limit theoreom, as appropriate, each student in a group does their own data generation and subsequent analysis, then shares their results within a group

**content of lab report** [60 points; henceforth, your group has about 1 week to do a lab report]

determine coefficient of static & kinetics friction as a function of __ [40 points]

mass

nature of surface

surface area of contact

wheels

include appropriate statistical analysis.

rationalize your preceding results [10 points]

relate ___ [10 points]

force, mass, and acceleration

acceleration and velocity

**resources**

lab info

statistical tests: mathematica; recommend not using versions prior to Excel 2010 (1; 2)