2. Solved Papers
  3. CET Karnataka Medical

CET Karnataka Medical CET - Karnataka Medical Solved Paper-2007

  • question_answer
    A prism of a certain angle deviates the red and blue rays by \[8{}^\circ \] and \[12{}^\circ \]respectively. Another prism of the same angle deviates the red and blue rays by \[10{}^\circ \] and \[14{}^\circ \]respectively. The prisms are small angled and made of different materials. The dispersive powers of the materials of the prisms are in the ratio

    A)  5 : 6

    B)  9 : 11

    C)  6 : 5

    D)  11 : 9

    Correct Answer: C

    Solution :

    Dispersive power, \[\omega =\frac{{{\delta }_{B}}-{{\delta }_{R}}}{\delta }\] For 1st prism,  \[{{\omega }_{1}}=\frac{{{\delta }_{B}}-{{\delta }_{R}}}{\delta }=\frac{{{12}^{o}}-{{8}^{o}}}{{{10}^{o}}}=\frac{2}{5}\] where   \[\delta =\frac{{{\delta }_{B}}+{{\delta }_{R}}}{2}\] Similarly, for 2nd prism, \[{{\omega }_{2}}=\frac{{{14}^{o}}-{{10}^{o}}}{12}=\frac{1}{3}\] \[\therefore \] \[\frac{{{\omega }_{2}}}{{{\omega }_{1}}}=\frac{2}{5}\times \frac{3}{1}=\frac{6}{5}\]


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