  The proper choice of a measurement technique that minimizes systematic and
random uncertainty is an essential part of experimental physics. These issues
are difficult to teach in the introductory laboratory, though: because most
experiments involve only a single measurement technique, students are often
unable to make a clear distinction between random and systematic uncertainties,
or to compare the uncertainties associated with different techniques. In this
paper, we describe an experiment suitable for an introductory college level (or
advanced high school) course that uses velocity measurements to clearly show
students the effects of both random and systematic uncertainties.
