JEE Main & Advanced Physics Atomic Physics Question Bank Topic Test - Atomic Physics

  • question_answer
    The wavelength of the energy emitted when electron come from fourth orbit to second orbit in hydrogen is \[20.397\,cm\]. The wavelength of energy for the same transition in \[H{{e}^{+}}\] is        

    A) \[5.099\ c{{m}^{-1}}\]

    B) \[20.497\ c{{m}^{-1}}\]

    C) \[40.994\ c{{m}^{-1}}\]

    D) \[81.988\ c{{m}^{-1}}\]

    Correct Answer: A

    Solution :

    [a] \[E\left( =\frac{hc}{\lambda } \right)\propto \frac{{{Z}^{2}}}{{{n}^{2}}}\] Þ \[\lambda \propto \frac{1}{{{Z}^{2}}}\]
    Hence \[{{\lambda }_{H{{e}^{+}}}}=\frac{20.397}{4}=5.099\,cm\]
     


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