Which disk is turning faster

B ovbiously its B,Its spinning way faster. Well when you look at the letter A The letter B slows down and vice versa and when you look at Letter B Letter A slows down so its hard to tell which is the fastest. A, for me. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment.

Posted on April 6, June 15, by James Dean. Published by James Dean. Prev Deserted Avenue Illusion. Next Embossed Footprints Illusion. I think B turns faster though :P. If u look at A, B spins faster…. If u look at B, A spins faster. A tee- hee. Its just the same color isnt it? At least it all looks green to me. Even if my formal language makes me one. What color do you see at the center? What about the next few bands? Reverse the direction of rotation and compare the order of colors again, from the center of the disk to the outer edge.

Try varying the speed of rotation and the size of the pattern, and compare the results with your initial observations. Different people see different intensities of colors on this spinning disk.

Why people see color here is not fully understood, but the illusion involves color vision cells in your eyes called cones. There are three types of cones. One is most sensitive to red light, one to green light, and one to blue light. Each type of cone has a different latency time the time in which it takes to respond to a color , and a different persistence-of-response time the time it keeps responding after the stimulus has been removed.

Blue-sensitive cones, for example, are the slowest to respond have the longest latency time , but they keep responding the longest have the longest persistence time. When you gaze at one place on the spinning disk, you are looking at alternating flashes of black and white. When a white flash goes by, all three types of cones respond. But your eyes and brain see the color white only when all three types of cones are responding equally.

The fact that some types of cones respond more quickly than others—and that some types of cones keep responding longer than others—leads to an imbalance that partly explains why you see colors. The colors vary across the disk because at different radial positions on the disk the black arcs have different lengths. As a result, the duration of the flash on the retina is also different. Like the cones of the eye, the three different color sensors in some color-television cameras also have different latency and persistence times.

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Benham's Disk A rotating black-and-white disk produces the illusion of color.