The critical angle of a medium for a specific wavelength, if the medium has relative permittivity 3 and relative permeability ${4 \over 3}$ for this wavelength, will be :
Solution
n = $\sqrt {{\varepsilon _r}{\mu _r}} = \sqrt {3 \times {4 \over 3}}$ = 2
<br><br>n sin c = 1 sin 90<sup>o</sup>
<br><br>sin c = ${1 \over 2}$
<br><br>$\Rightarrow$ c = 30<sup>o</sup>
About this question
Subject: Physics · Chapter: Optics · Topic: Total Internal Reflection
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