Explain geometrical illusions.

Geometrical illusions: Muller-Lyer illusion has given illusion figures. In the figures given below all of us perceive line A as shorter than line B, although both the lines are equal. This illusion is experienced even by children. There are some studies that suggests that even animals experience this illusion more or less like us. Besides Muller-Lyer illusions, several other visual illusions are experienced by human beings (also birds and animals). In the vertical-horizontal illusion the illusion of vertical and horizontal lines can be seen. Although both the lines are equal, we perceive the vertical line as longer than the horizontal line.

Fig. Muller-Lyer Illusion