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At what angle should two plane mirrors be placed so that a single object forms three images?

1. 60°
2. 90°
3. 120°
4. 30°

Correct answer: 90°

Solution

When two plane mirrors are positioned at a 90° angle to each other, they create multiple reflections that result in three distinct images of the object. This occurs because each mirror reflects the image created by the other, leading to a total of three visible images.

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