Figures 13-18b and 13-18c show the next two standing wave modes of a closed pipe, and Figure 13-19 shows the displacement patterns extended outside the pipe. You can see that three quarters (3/4) and five quarters (5/4) of a wavelength, respectively, fit into the pipe for these modes. You can also see that the general relationship between \(L\) and \(\lambda\) for a closed pipe is