The observed image velocity of a stationary target reflected by a rotating plane mirror.
An equation is presented describing the angular velocity of an image, viewed by an observer when a plane mirror is undergoing angular velocity. The image velocity is determined at the observer's entrance pupil. An expression to determine the size of the mirror aperture for a given exposure time is also presented. The results indicate that, in general, the image velocity is not constant nor twice the mirror velocity, as is usually assumed. Also, if the mirror extends to an equal length on each side of its axis of rotation, then the time in which the image appears to travel from the mirror's edge to the axis of rotation does not equal the time in which it appears to travel from the axis to the other edge.
D006801:Humans; D008433:Mathematics; D010775:Photic Stimulation; D012399:Rotation; D014796:Visual Perception / Q000502:physiology*