In interference of light, dark and bright bands are seen on the screen. Do this phenomenon violate the law of conservation of energy? Explain.

In interference and diffraction of light, dark and bright bands are seen on the screen.In an interference pattern, the ratio of maximum intensity to minimum intensity is 36:9. Find the ratio of amplitudes and intensities of the two interfering waves.

In interference, when light energy superimpose with a phase difference 180°, darkness occurs.Does interference phenomenon violate law of conservation of energy? Justify.