Final answer:
The question demonstrates the law of reflection. In a setup where two flat mirrors are set edge-to-edge and perpendicularly, a ray of light reflecting off the mirrors will travel in a direction exactly opposite its initial direction irrespective of the its angle of incidence. Such a system is often used in clothing stores for a clear, non-reversed reflection.
Step-by-step explanation:
This question is about the physics concept of the law of reflection, which states that the angle of reflection is equal to the angle of incidence. When a light ray hits a flat, rectangular mirror at an arbitrary angle of incidence, θ₁, it will reflect off the mirror at the same angle, θ₁, relative to the normal (the line perpendicular to the point at which the light ray strikes).
Now, when this ray strikes a second mirror set edge to edge with the first mirror and also perpendicular to it, it again follows the law of reflection. It reflects at an angle same as its angle of incidence on the second mirror. Due to the perpendicular arrangement of the mirrors, these two reflections cause the final direction of the ray to be exactly opposite of the initial direction. Such a pair of mirrors are often used in clothing stores, where without any apparent right-left reversal, they show you an image of yourself as others see you-
This concept is often seen in corner reflectors, objects consisting of two mutually perpendicular surfaces that reflect light back in a direction parallel to its initial direction.
This apparent reversal of direction is independent of the angle of incidence, and occurs anytime the reflecting surfaces are perpendicular.
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