* Mirrors Reverse Left and Right, Not Up and Down: When you stand in front of a mirror, your reflection appears to be reversed left to right. This is because light reflects off the mirror surface, flipping the image horizontally.
* Perpendicular Mirrors Create a Double Reflection: When you have two mirrors at a 90-degree angle, your image is reflected twice. The first reflection flips your image left to right. Then, the second reflection flips the already flipped image, effectively reversing the second flip.
The Illusion:
Since the second reflection flips the image back to its original orientation, it appears as though your left hand is on the right side in the final image. However, the actual image has been flipped twice and is still mirrored left to right.
In Conclusion:
The left hand appearing on the right in perpendicular mirrors is a result of the double reflection process, creating the illusion of a reversed image. The image is still mirrored left to right, it's just that the two reflections cancel each other out in terms of left-right orientation.