Uncertainty analysis and instrument selection using a web-based virtual experiment

Abstract

This paper presents details of a web-based virtual experiment designed to teach students about selection of instruments based on the uncertainty estimated from the virtual experiment. The web-based virtual experiment, involves measurement of frictional losses in a fluid flowing in a pipe at various flow rates. Using the virtual module, a student experimenter can adjust the flow rate in the pipe with a virtual flow control valve and measure both the flow rate and the pressure drop by selecting different measuring instruments. The selected instruments have their inherent measurement uncertainties and the student is tasked through various activities in the virtual experiment to evaluate which instrument is the "best fit" for the particular experimental design situation. The web-based virtual module has been implemented and assessed for student learning effectiveness related to measurement uncertainties and instrument selection. Student learning gains achieved through the web-based virtual module were measured by comparing the performance of two "Control" groups (no access to the module) and an " Experimental" group with access to the web-based virtual module. All three groups were administered an identical multiple choice quiz and the quiz scores were analyzed to gage the effectiveness of the module in teaching students about instrument selection, and uncertainties and errors in experiments. Analysis of assessed data indicates that student learning gains due to incorporation of the virtual module are statistically significant.