• An oil slick is formed by placing a drop of oil on water surface. As per the wave theory of light, the patterns and colors on the oil slick are attributed to the interference of waves from the upper and the lower surface of the oil slick. 

 

  • But the experiments by the author have revealed that the pattern on the oil slick is on account of fluid layer on the oil slick forming the surface pattern. these patterns vary depending on the nature of the surface and the thickness of the oil slick. 

 

  • In figure Fig-3a the pattern is formed by placing a watch glass just above the oil slicks on the surface of water in a dish. Three distinct Newton's rings or distorted Newton's rings patterns are seen. 

 

  • The first pattern is the surface pattern on the oil slick and the second one is the pattern formed in the complex fluid between the oil slick and the watch glass and the third pattern os due to the complex fluid between the water surface and the watch glass surface.

 

  • The surface pattern on an oil slick formed on water surface is shown in Fig-3b.

 

Fig-3a.

Fig-3b.