Question

There is a small air bubble inside a glass sphere (µ = 1.5) of radius 10 cm. The bubble is 4 cm below the surface and is viewed normally from outside. The apparent depth of the bubble is

Answer 1

Answer:

The bubble will appear 3.03 cm below the surface.

Explanation:

Given that,

Refractive index $\mu_{1}=1.5$

Refractive index $\mu_{2}=1$

Radius = -10 cm

The bubble is 4 cm below the surface and is viewed normally from outside.

$u= -4 cm$

Using formula of refractive index

$\dfrac{\mu_{2}}{v}-\dfrac{\mu_{1}}{u}=\dfrac{\mu_{2}-\mu_{1}}{R}$

$\dfrac{1}{v}-\dfrac{1.5}{-4}=\dfrac{1-1.5}{-10}$

$\dfrac{1}{v}= \dfrac{0.5}{10}-\dfrac{1.5}{4}$

$v= -3.03\ cm$

Hence, The bubble will appear 3.03 cm below the surface.

Answer 2

Answer:

Explanation:

µ = 1.5 , radius 10 cm

Formulae:

µ2/v - µ1/u  = µ2-µ1/r

1/v - 1.5/-40 =  1-1.5/-10

 1/v = 0.5/10 - 1.5/4

v=1.3cm

Bubble will be 3 cm below the surface.

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