Question

Under what condition in an arrangement of two plane mirrors, incident ray and reflected ray will always be parallel to each other, whatever may be angle of incidence. Show the same with the help of diagram.​

Answer 1

when the two mirrors are placed at right angles the incident ray and the reflected ray are always parallel to each other, whatever may be the angle of incidence

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Answer 2

$\large\bf\red{Explanation✓}$

If two plane mirrors are placed perpendicular to each other then Incident ray and reflected ray will always be parallel to each other.