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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°.
Solution
- For θ1 = 35°
n1 = `360/θ_1=360/35` = 10.28
As n1 is non-integer, N1 = integral part of n1 = 10 - For θ2 = 36°
n2 = `360/36` = 10
As n2 is even integer, N2 = (n2 – 1) = 9 - 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) - 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.
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