We shall explore the physical characteristics of standing waves by considering
transverse waves on a taut string. The string is stretched between two fixed points,
which we take to be at x = 0 and x = L, respectively. The transverse displacement
of the string is in the y-direction. An example of such a standing wave is illustrated
in Figure 6.1. Snapshots of the string at successive instants of time are shown in
Figure 6.1(a)–(e), while Figure 6.1(f) shows these individual snapshots on a single
set of axes. The displacement y is always zero at x = 0 and x = L since the
string is held fixed at those points. However, midway between the fixed ends we
can see that the displacement of the string is also zero at all times. This point is
called a node. Midway between this node and each end point the wave reaches its
maximum displacement. These points are called antinodes. The positions of these