References

Wagon wheel effect

WikiPedia.org; Internet Reference, 2010.

The wagon-wheel effect (alternatively, or stagecoach-wheel effect, stroboscopic effect) is an optical illusion in which a spoked wheel appears to rotate differently from its true rotation. The wheel can appear to rotate more slowly than the true rotation, it can appear stationary, or it can appear to rotate in the opposite direction from the true rotation. This last form of the effect is sometimes called the reverse rotation effect.

Web Resource: en.wikipedia.org

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