Thus a thin glass plate or a thin soap bubble will reinforce only a particular color for a particular thickness, but over a large surface will reflect a brilliant rainbow from incoming white light. The frequency of that vibration determines whether the wave is a radio wave, light, an x-ray, or other electromagnetic wave. A to 7000 A, from violet to red. In the problems that follow assume the l given or asked for is that within the thin layer. Two glass plates are placed together so as to leave a narrow air gap between them.
Oil has an optical density between air and water.
I hope you've noticed an apparent inconsistency. The term interference is used to describe the interaction of waves. Destructive interference is the cancellation on wave energy. Constructive interference is the reinforcement of waves. What we have been looking at interference from very thin layers of material is called thin film interference .