Two plane mirrors are inclined at 60°. The number of images of a small object placed between them is:
A5
BInfinitely many
C6
D7
Answer & Solution
Correct answer: A. 5
For two plane mirrors inclined at an angle θ (with 360° divisible by θ), the number of images is given by n = (360°/θ) − 1. With θ = 60°: n = (360°/60°) − 1 = 6 − 1 = 5. (When the mirrors are PARALLEL, θ → 0 and the number of images is infinite — what you see in a barbershop or fitting room.)
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