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Total Internal Reflection and Critical Angle - Class XII
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Critical angle of glass is $\theta _1$ and that of water is $\theta _2$. The critical angle for water and glass surface would be $(\mu _g=3/2, \mu _w=4/3)$
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A
greater than $\theta _2$
💡 Explanation:
At critical angle. $\mu _{dense} \times sin \theta _ {dense} = \mu _{rare} \times sin 90°$
For glass - air: $(3/2) \times Sin \theta _ {1} = 1 => \theta _{1} = 41.81 ^\circ$
For water - air: $ (4/3) \times Sin \theta _ {2} = 1 => \theta _{2} = 48.59^\circ$
For water- glass, glass is denser: $ (3/2) \times Sin \alpha = (4/3)$ => $ \alpha = 62.72^\circ$