Question

Does the principle of conservation of energy hold for interference and diffraction phenomena? Explain briefly.

Answer 1

Yes law of conservation of energy is obeyed. In case of constructive interference, intensity becomes maximum and bright fringes are formed in the screen whereas in case of destructive interference, intensity being minimum, dark fringes are formed. This implies that in interference and diffraction pattern, the intensity of light is simply being redistributed i.e. energy is only transferred from dark to bright fringe and no energy is created or destroyed in the process.