NEET Sample Paper NEET Sample Test Paper-51

  • question_answer
    The refractive index of water is 4/3 and that of glass is 5/3. Then the critical angle for a ray of light entering water from glass will be-

    A) \[si{{n}^{-}}^{1}\left( 4/5 \right)\]                   

    B) \[{{\sin }^{-}}^{1}\,\,\left( 5/4 \right)\]

    C) \[si{{n}^{-}}^{1}\left( 20/9 \right)~\]   

    D) \[si{{n}^{-1}}\,\,\left( 9/20 \right)\]

    Correct Answer: A

    Solution :

    \[{{\mu }_{w}}=\frac{4}{3}\,\,{{\mu }_{glass}}\,\,=\,\,\frac{5}{3}\] glass is denser medium wrt water. \[{{\theta }_{c}}\,\,=\,\,{{\sin }^{-1}}\,\left( \frac{{{\mu }_{r}}}{{{\mu }_{D}}} \right)\] \[{{\theta }_{c}}\,\,=\,\,{{\sin }^{-1}}\,\left( \frac{\frac{4}{3}}{\frac{5}{3}} \right)\] \[{{\theta }_{c}}\,\,=\,\,{{\sin }^{-1}}\,\left( \frac{4}{5} \right)\]


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