Answer to Question #135876 in Optics for Max

Question

Write note on interference?

Answer 1

Interference is the variation of wave amplitude with distance or time, caused by the superposition of two or more waves. As most common used, the term refers to the interference of waves of the same or nearly the same frequency. Wave interference is characterized by the phenomenon of the occurrence of local maxima and minima of wave amplitude, which cannot be described by the ray approximation to solutions of the wave equation. In terms of Huygens’ principle, interference can occur whenever wave disturbance can be propagated from a source to a region of space by two or more paths of different length. There is destructive interference if the phases and amplitudes of the disturbances arriving by the various routes are such as to reduce the square of the resultant amplitude, below the sum of the squares of the amplitudes of the components. Two or more sources may only be used if there is a fixed phase-relation between them. Sound interference results when the waves concerned are sound waves. Optical interference occurs with light waves.