For a standing wave, the antinodes are the points in space where the amplitude of oscillation is maximum. For example, given the standing wave


\begin{displaymath}\eta(x,t) = A\cos(kx)\cos(\omega t), \notag
\end{displaymath}  

where $A$ is the wave amplitude, $k$ is the wavenumber, $\omega $ is the wave frequency, $x$ is the space paremeterization and $t$ is the time parameterization. For the positions where $\eta$ is maximum (antinodes), we have


\begin{displaymath}x = \frac{2n\pi}{k} \mbox{\ with\ } n \mbox{\ an integer} \notag
\end{displaymath}  



Timothy S Choe
2003-03-15