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For a diven medium, the polarising angle...

For a diven medium, the polarising angle is `60^(@)`. What will be the critical angle for this medium ?

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To find the critical angle for a medium where the polarizing angle is given as \(60^\circ\), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding Polarizing Angle**: The polarizing angle (\(I_p\)) is the angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection. According to Brewster's Law, the polarizing angle is related to the refractive index (\(n\)) of the medium. 2. **Using Brewster's Law**: Brewster's Law states that: \[ \tan(I_p) = n \] Given that \(I_p = 60^\circ\), we can find the refractive index: \[ n = \tan(60^\circ) \] 3. **Calculating the Refractive Index**: We know that: \[ \tan(60^\circ) = \sqrt{3} \] Therefore, the refractive index \(n\) of the medium is: \[ n = \sqrt{3} \] 4. **Finding the Critical Angle**: The critical angle (\(I_c\)) can be calculated using the formula: \[ I_c = \sin^{-1}\left(\frac{1}{n}\right) \] Substituting the value of \(n\): \[ I_c = \sin^{-1}\left(\frac{1}{\sqrt{3}}\right) \] 5. **Calculating the Critical Angle**: We know that: \[ \frac{1}{\sqrt{3}} \approx 0.577 \] Using a calculator or trigonometric tables, we find: \[ I_c \approx 35.26^\circ \] 6. **Conclusion**: Therefore, the critical angle for the medium is: \[ I_c \approx 35.26^\circ \] ### Final Answer: The critical angle for the medium is approximately \(35.26^\circ\). ---
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