Question

Solve Numerical example.

Estimate the number of images produced if a tiny object is kept in between two plane mirrors inclined at 35°, 36°, 40° and 45°.

Answer 1

1. For θ₁ = 35°
   n₁ = `360/θ_1=360/35` = 10.28
   As n₁ is non-integer, N₁ = integral part of n₁ = 10
2. For θ₂ = 36°
   n₂ = `360/36` = 10
   As n₂ is even integer, N₂ = (n₂ – 1) = 9
3. or θ₃ = 40°
   n₃ = `360/40` = 9
   As n₃ is odd integer,
   Number of images seen (N₃) = n₃ – 1= 8
   (if the object is placed at the angle bisector)
   or Number of images seen (N₃) = n₃ = 9
   (if the object is placed off the angle bisector)
4. For θ₄ = 45°
   n₄ = `360/45` = 8
   As n₄ is even integer,
   N₄ = n₄ – 1 = 7

The number of images seen when mirrors are inclined at 35°, 36°, 40°, 45° are 10, 9, 8 or 9, 7 respectively.