Optics Question 85
Question: One face of a rectangular glass plate 6 cm thick is silvered. An object held 8 cm in front of the first face, forms an image 12 cm behind the silvered face. The refractive index of the glass is
[CPMT 1999]
Options:
A) 0.4
B) 0.8
C) 1.2
D) 1.6
Show Answer
Answer:
Correct Answer: C
Solution:
Let x be the apparent position of the silvered surface.
According to property of plane mirror x + 8 = 12 + 6 - x
$ \Rightarrow $ x = 5 cm
Also $ \mu =\frac{t}{x} $
$ \Rightarrow $ $ \mu =\frac{6}{5}=1.2 $
