MCQ
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
- A$0.4$
- B$0.8$
- ✓$1.2$
- D$1.6$
✓
Answer
Correct option: C.
$1.2$
c
(c) Let $ x$ be the apparent position of the silvered surface.
(c) 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$
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