Examples of Measurement and Uncertainty

Initial Publication Date: November 4, 2009

students measuring temperature of compressed gas as it is released from can
Three types of activities are included with this module:

1. Instructional packets that serve the purpose of a student guide for teaching effective measurement:
Introduction to Measurement (advanced high school/intro college level) A 30-page instructional packet intended to teach advanced high school or introductory level college students the fundamentals of effective measurement

Introduction to Measurement in the Physics Laboratory. A Probabilistic Approach, Ed. 3.4 A. Buffler, S. Allie, F. Lubben, and B. Campbell, (Department of Physics, University of Cape Town, 2007). A 140-page document intended to teach effective measurement technique to college science majors.
2. Activities designed to help students practice and solidify their understanding uncertainty and effective measurement:
Activity: Measuring your reaction time A short lab activity where students collect data to practice effective measurement technique and express results as a range of possible values.

Activity: Identifying a solid using density A lab activity where students make measurements to determine density of solids. This activity is an opportunity for students to practice effective measurement technique.
3. Examples of labs that incorporate effective measurement technique:
Determining Measured Values and Uncertainty Students practice reading various measurement devices, such as graduated cylinders, electronic balances, voltmeters and spring scales. In each case students determine the range of possible values for the measurement. They express this range as a measured value with uncertainty in three forms, including a number line with error bars.

Performing Calculations using Measured Values that Include Uncertainty Students measure the mass and volume of pennies and use the values to calculate the density of the pennies. All measured values include uncertainty, and students practice using the rules for making calculations using numbers that include uncertainty.

Lab: Horizontally Launched Projectiles (with uncertainty analysis) This is a traditional lab taught by many physics instructors. Students roll a ball off a table and predict where it will land. In this version, students use effective measurement technique as presented in this module.

Lab: Speed of Sound in Air (with uncertainty analysis) This is a traditional lab taught by many physics instructors. Students use a microphone and Vernier LabQuest to record the sound of a finger snap echoing in a cardboard tube 1 to 2 meters long. Students measure the time for the sound to return to the microphone and use this to determine the speed of sound. Although other authors have produced similar labs, this one incorporates effective measurement technique consistent with this module.