Figure 13-7 also shows something remarkable about waves: \(\textit{During the time that it takes an individual piece of the medium to complete one cycle of oscillation, the wave travels a distance of one wavelength through the medium}\). We can use this observation to relate the wavelength and frequency to the \(\textit{speed}\) of the wave. Since the wave travels a distance \(\lambda\) in a time \(T\), the \(\textbf{propagation speed}\) \(v_{\mathrm{p}}\) of the wave is