Question
A light wave is reflected from the mirror. The incident and the reflected waves superimpose to form stationary wave, but the nodes and anti-nodes are not seen. Why?
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Answer
The distance between successive nodes or anti-nodes is $\frac{\lambda}{2}.$ The wavelength $(\lambda)$ of the light is of the order of 10-m, so the distance between successive nodes or antinodes is also of the order of 10-7m. Since this distance is very small and cannot be detected by the eye or by an ordinary optical instrument, Hence nodes and antinodes are not seen.
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