The film of oil on water shows color pattern when illuminated by white light due to:

Explanation

The film of oil on water shows a color pattern when illuminated by white light due to interference.Interference is a phenomenon in which two waves superimpose to form a resultant wave of greater, lower, or the same amplitude. In the case of a thin film of oil on water, the light waves reflected from the top and bottom surfaces of the film interfere with each other. The colors that we see are due to the constructive and destructive interference of the light waves.Constructive interference occurs when the waves are in phase, and the resulting wave has a larger amplitude.Destructive interference occurs when the waves are out of phase, and the resulting wave has a smaller amplitude.The color pattern that we see depends on the thickness of the oil film and the wavelength of the light. The different colors of light have different wavelengths, so they will interfere in different ways. This is why we see a rainbow of colors when we look at a thin film of oil on water.