Demonstration of the propagation of errors using resistors

Abstract

We present a simple experiment to demonstrate the concept of propagation of errors by measuring resistors on printed circuit boards (PCBs). We devise a method for connecting the resistors on a PCB that allows a relatively quick measurement of 200 resistor pairs to show that the distributions of the measurement of individual resistances, as well as the total resistance, are Gaussian-distributed, as expected from the central limit theorem. The measurement demonstrates how individual uncertainties propagate to the total uncertainty. The experiment is part of a laboratory course on statistics for physics students that emphasizes the application of statistics in data analysis.