A thin layer of oil floats on a water puddle. An observer sees a colored pattern. This happens because
A) two surfaces each transmit some light and reflect some light.
B) oil always does this, even if it is not on water.
C) water transmits light and never reflects light.
D) sunlight's frequency range shifts to infrared at the boundary of water and oil.

Question

Quizplus · Accepted Answer

When light passes through the oil layer, some of it is transmitted and some is reflected. The same thing happens when the light reaches the water surface - some is transmitted and some is reflected. The reflected light interferes with the transmitted light, creating a pattern of colors that we see. This is known as thin-film interference.

A Thin Layer of Oil Floats on a Water Puddle