2. Questions Bank
  3. JEE Main & Advanced
  4. Physics
  5. Semiconducting Devices

JEE Main & Advanced Physics Semiconducting Devices Question Bank Self Evaluation Test - Semiconductor Electronics: Materials, Devices and Simple Circuits

  • question_answer
    The ratio of electron and hole currents in a semiconductor is \[7/4\] and the ratio of drift velocities of electrons and holes is \[5/4,\] then ratio of concentrations of electrons and holes will be

    A)  \[5/7\]

    B)  \[7/5\]   

    C)  \[25/49\]

    D)  \[49/25\]

    Correct Answer: B

    Solution :

    [b] \[I=nAe{{v}_{d}}\] or \[I\propto n{{v}_{d}}\] \[\therefore \,\,\,\,\,\,\,\frac{{{I}_{e}}}{{{I}_{h}}}=\frac{{{n}_{e}}{{v}_{e}}}{{{n}_{h}}{{v}_{h}}}\] or \[\frac{{{n}_{e}}}{{{n}_{h}}}=\frac{{{I}_{e}}}{{{I}_{h}}}\times \frac{{{v}_{h}}}{{{v}_{e}}}=\frac{7}{4}\times \frac{4}{5}=\frac{7}{5}\]


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