Single Choice

An air bubble in a glass with refractive index $$1.5$$ (near normal incidence) i.e. $$5\ cm$$ deep when viewed from one surface and $$3\ cm$$ deep when viewed from the opposite face. The thickness(in $$cm$$) of the is.

A$$16$$
B$$8$$
C$$10$$
D$$12$$
Correct Answer

Solution

The apparent dept of bubble as seen from one surface=$$\dfrac{d_1}{\mu}=5cm $$

$$\implies$$ Real depth of bubble from one surface $$d_1=7.5cm$$

Similarly real depth of bubble from other surface=$$d_2=1.5\times 3cm=4.5cm$$

Hence the thickness of the glass is $$d_1+d_2=12cm$$

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