The core principle governing these phenomena is wave-particle duality and optical interference, where light behaves as a superposition of electromagnetic waves described by Huygens' Principle. The theory defines constructive interference occurring when the path difference between coherent sources equals an integer multiple of the wavelength ($n\lambda = D \sin\theta$), resulting in bright fringes, while destructive interference arises at half-integer multiples causing dark regions via amplitude cancellation. This concept belongs to wave optics within physics and serves as a mechanism for analyzing spectral composition through diffraction gratings based on precise geometric conditions of phase alignment.
The core principle governing these phenomena is wave-particle duality and optical interference, where light behaves as a superposition of electromagnetic waves described by Huygens' Principle. The th…