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Question
Two plane mirrors are placed making an angle θ in between them. Write an expression for the number of images formed of an object placed in between the mirrors. State the condition, if any.
Solution
If two mirrors make an angle with each other and object is placed in between the two mirrors, the number of images formed is n or (n - 1) depending upon n = 360o / o is odd or even.
(a) If n = 360o / o is odd,
(i) The number of images formed is n, when the object is placed asymmetrically between the mirrors.
(ii) The number of images formed is n-1, when the object is placed symmetrically between the mirrors.
(b) If n = 360o / o is even, the number of images is always n-1.
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