How does the eye see colors that are moving very rapidly?
I am assuming you mean a color wheel made up of several colored segments that spins rapidly and appears as a single color. That is called a Maxwell disk. Maxwell used such a device to study how the human visual system perceives color and determined that all colors can be matched by additive combinations of three primaries. What happens is that the disk is spinning so quickly that we are no longer able to resolve the individual segments and they blur together. The color effect is the same as superimposing three projected lights and is known as additive color mixing. There is a good explanation/description at www.handprint.com. Another way colors are produced with spinning disks is by using black-and-white patterns that result in different stimulation of the three cone types in our eyes and thus produce colors where there physically are none. That demonstration is known as Benham’s disk (as well as other names). A demonstration is described at exploratorium.edu. Web searches on either of
