Question 383: Ray Optics

Question

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index

Accepted Answer

According to lens maker's formula
$${1 \over f} = \left( {{{{\mu _g}} \over {{\mu _L}}} - 1} ight)\left( {{1 \over {{R_1}}} - {1 \over {{R_2}}}} ight)$$
As the biconvex lens dipped in a liquid acts as a plane sheet of glass, therefore
f = $$\infty $$ $$ \Rightarrow $$ $${1 \over f} = 0$$
$$ 	herefore $$ $${{{{\mu _g}} \over {{\mu _L}}} - 1 = 0}$$
$$ \Rightarrow $$ $${{\mu _g} = {\mu _L}}$$

Answer

equal to that of glass

Answer

less than one

Answer

greater than that of glass

Answer

less than that of glass

Ray Optics

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index

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