What is the colour of a red flower when it is exposed to blue light?
(Saijune, Manama, Bahrain) Galego, a red flower of Galicia, Spain. Photo by Luis Miguel Bugallo Snchez. Used with permission. A: The red petals appear black in blue light, because they reflect red light. If I illuminate the red petals in blue light only, then there is no red light to reflect to my eyes and, therefore, the red petals appear black the absence of light. Now, for a couple of qualifiers: the petals will contain some blue color; also blue lights emit a tiny amount of red light. Thus, the red (with a trace of blue color) petals will reflect some blue light and, therefore, not appear exactly black more grayish. Also, the petals will reflect the small amount of red light emitted by the ‘blue’ light. So, the color will actually be dark gray with a tinge of red. Further Reading: Color perception by Rod Nave Color and vision by Tom Henderson, Glenbrook South High School, Glenview, Illinois (Answered Oct.
