The Caliper

 Innovative Uses

Two-Liter Creek

John Fischer, Ashwaubenon HS, Green Bay, WI, has created an artificial “Two Liter Creek” in his classroom for water quality studies in the middle of a Wisconsin winter. It is simply a 50-gallon aquarium with a pump that lifts water into an array of 15 two-liter bottles that have been mounted on a pegboard. This closed-loop creek has gravel in the bottles and in the aquarium. Over time, the artificial creek forms an ecosystem, as does a real creek. John’s students become experts at using our sensors to monitor this creek and they are ready to tackle the outdoor water when spring comes. The students have even intentionally “polluted” the creek and monitored its recovery.

Hot Biceps
Judy Day (The Science House, Raleigh, NC) has students and workshop participants use our new Surface Temperature Sensor to examine the increase of muscle temperature as a team member lifts a 2-3 lb (1 kg) weight. The Surface Temperature Sensor is designed for use in situations in which low thermal mass and/or flexibility is required. It has an exposed thermistor that results in an extremely rapid response time; therefore, it is ideal for this experiment.

A student places the tip of the temperature against the bicep muscle for at least one minute to allow the probe to equilibrate with the skin and muscle’s temperature. Meanwhile, another student sets up the data collection for a 3-minute experiment, taking one reading every second. Once the temperature has stabilized, data collection is started. After collecting muscle temperature for about 15 seconds, the student begins lifting the weight (curling the arm), while another student continues holding the Surface Temperature Sensor against the muscle.

When the data collection has ended, students are asked to explain why the muscle temperature has increased by 1.5 to 3° C. As an extension, Judy also uses Logger Pro software and our Exercise Heart Rate Monitor to track heart rate during this experiment.

Darren Carollo’s, students (Lincoln HS, Dallas, TX) learn about high- energy physics by doing hands-on experiments. Among other experiments, the students use a CO 2 fire extinguisher to shoot a piece of bubble gum through the tube and smash it inside a Plexiglas® box. The students measure the speed of the particles in this “particle accelerator” using two Vernier Photogates and LabPro.

Frances Van Dyke authored the article “Using Graphs to Introduce Functions” in the February, 2003 issue of Mathematics Teacher. She describes how a Motion Detector can be used to help students understand the concept of functions. She starts with qualitative graphs and progresses to quantitative graphs, then data tables, and then equations. The article contains a complete set of worksheets for this lesson.

As is usually the case, recent issues of The Physics Teacher have had a lot of great ideas for using data collection. Here are some examples:

January 2003: “Measuring the Damping Constant for Under-Damped Harmonic Motion,” Michael C. LoPresto and Paul R. Holody, Henry Ford Community College, Dearborn, MI. They use LabPro to do a nice study of a spring-mass system.

February 2003: “Simple Uncertainty-Principle Experiment,” Charles A. Sawicki, North Dakota State University, Fargo. He uses Logger Pro and a microphone to gather data and do some analysis to introduce modern physics concepts.

March 2003: “How Fast Is Your Finger? An Introduction to Photogate Use,” John Gardner, Eastern Illinois University, Charleston, IL and Mattoon HS, Mattoon, IL. He offers some simple activities that you might want to try the first time you use photogates with your students.