BCECE Medical BCECE Medical Solved Papers-2012

  • question_answer
    If an electron jumps from the 4th orbit to the 2nd orbit of hydrogen atom, then the frequency of emitted radiation in the hertz will be (Take Rydbergs constant, \[R={{10}^{5}}\,c{{m}^{-1}}\])

    A)  \[\frac{3}{4}\times {{10}^{15}}\]

    B)  \[\frac{3}{16}\times {{10}^{15}}\]

    C)  \[\frac{3}{16}\times {{10}^{15}}\]

    D)  \[\frac{9}{16}\times {{10}^{15}}\]

    Correct Answer: D

    Solution :

    Using the relation,                 \[\frac{1}{\lambda }=R\left( \frac{1}{n_{1}^{2}}-\frac{1}{n_{2}^{2}} \right)\]                 \[={{10}^{-5}}\left( \frac{1}{{{2}^{2}}}-\frac{1}{{{4}^{2}}} \right)\]                 \[={{10}^{-5}}\times \left( \frac{1}{4}-\frac{1}{16} \right)\]                 \[\lambda =\frac{16}{3}\times {{10}^{-5}}\,cm\] \[\therefore \] Frequency, \[\therefore \eta =\frac{c}{\lambda }\]                 \[=\frac{3\times {{10}^{10}}}{\frac{16}{3}\times {{10}^{-5}}}\] \[=\frac{9}{16}\times {{10}^{15}}Hz\]


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