Vertical-Horizontal Illusion
VerticalHorizontalIllusion
The horizontal line segment in the above figure appears to be shorter than the vertical line segment, despite the fact that it has the same length.
See also
Illusion, Müller-Lyer Illusion, Poggendorff Illusion, Ponzo's IllusionExplore with Wolfram|Alpha
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References
Fineman, M. The Nature of Visual Illusion. New York: Dover, p. 153, 1996.Referenced on Wolfram|Alpha
Vertical-Horizontal IllusionCite this as:
Weisstein, Eric W. "Vertical-Horizontal Illusion." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Vertical-HorizontalIllusion.html