Student understanding of wave behavior at a boundary: The relationships among wavelength, propagation speed, and frequency

Abstract

This paper reports on the second part of an investigation of student understanding of wave behavior. A previous paper focused on the reflection of pulses from fixed and free ends. In this paper the focus is on the more complicated behavior of periodic waves at a boundary between two different media. We identified several erroneous reasoning approaches. Many students treated the relationship ν = λf as a mathematical identity, and did not recognize how the variables wavelength, frequency, and propagation speed can be manipulated experimentally. Many difficulties do not appear to be limited to the context of refraction of waves at a boundary, but seem to hinder student understanding of more advanced physics phenomena such as interference and diffraction.