Since the vibration of a single pendulum is very periodic, measuring its period is a very interesting topic. When students are asked to measure the period of a single vibration, they start and stop the stopwatch when the pendulum reaches the top point as a reference point. In this paper, we try to show that the error can be reduced more by using…

A low-cost and simple setup to measure the densities of liquids is introduced herein. The results and reliability of this setup were evaluated for pure liquids, water-ethanol binary mixtures, and aqueous NaCl solutions. The constructed densitometer provided density values with acceptable relative errors (less than ±3.0%), which were compared to…

Smartphones and tablets are used as experimental tools and for quantitative measurements in two traditional laboratory experiments for undergraduate physics courses. The Doppler effect is analyzed and the speed of sound is determined with an accuracy of about 5% using ultrasonic frequency and two smartphones, which serve as rotating sound emitter…

Argues against a rule-based, algorithmic approach to measurement in introductory chemistry courses. Describes a learning activity that leads students to understand the need for rules and the application of those rules in measurement. (DDR)

Contends that the nature of physics has been misrepresented by blurring or ignoring important distinctions between "errors" and "discrepancies" and that dealing with these and related problems can improve students' enjoyment of labs and understanding of physics. Nature of physics, role of experiments, experimental errors, and error analysis are…

Outlines the simple exercise of measuring the length of an object as a concrete paradigm of the entire process of making chemical measurements and treating the resulting data. Discusses the procedure, significant figures, measurement error, spurious data, rejection of results, precision and accuracy, and student responses. (TW)

In this paper, performance assessments are cast within a sampling framework. A performance assessment score is viewed as a sample of student performance drawn from a complex universe defined by a combination of all possible tasks, occasions, raters, and measurement methods. Using generalizability theory, the authors present evidence bearing on the…