JEE Main & Advanced Physics Ray Optics Question Bank Total Internal Reflection

  • question_answer
    If light travels a distance x in \[{{t}_{1}}\]sec in air and 10 x distance in \[{{t}_{2}}\]sec in a medium, the critical angle of the medium will be                                                                                                 [MH CET 2003]

    A)            \[{{\tan }^{-1}}\left( \frac{{{t}_{1}}}{{{t}_{2}}} \right)\]       

    B)            \[{{\sin }^{-1}}\left( \frac{{{t}_{1}}}{{{t}_{2}}} \right)\]

    C)            \[{{\sin }^{-1}}\left( \frac{10{{t}_{1}}}{{{t}_{2}}} \right)\]   

    D)            \[{{\tan }^{-1}}\left( \frac{10{{t}_{1}}}{{{t}_{2}}} \right)\]

    Correct Answer: C

    Solution :

                       From the formula \[\sin C=\frac{1}{_{1}{{\mu }_{2}}}\]\[\Rightarrow \sin C{{=}_{2}}{{\mu }_{1}}\]                    \[=\frac{{{u}_{1}}}{{{u}_{2}}}=\frac{{{v}_{2}}}{{{v}_{1}}}\]\[\Rightarrow \sin C=\frac{10x/{{t}_{2}}}{x/{{t}_{1}}}\]            \[\Rightarrow \sin C=\frac{10\,{{t}_{1}}}{{{t}_{2}}}\]\[\Rightarrow C={{\sin }^{-1}}\left( \frac{10\,{{t}_{1}}}{{{t}_{2}}} \right)\]


You need to login to perform this action.
You will be redirected in 3 sec spinner