2. Solved Papers
  3. NEET
  4. Physics
  5. Semiconducting Devices

NEET Physics Semiconducting Devices NEET PYQ-Semiconducting Devices

  • question_answer
    A transistor is operated in common-emitter configuration at \[{{V}_{c}}=2\] volt such that a change in the base current from \[100\,\mu A\] to \[200\,\mu A\]produces a change in the collector current from 5 mA to 10 mA. The current gain is                                                                                                                                            [AIPMT (S) 2009]

    A)  75

    B)              100                

    C)  150        

    D)  50

    Correct Answer: D

    Solution :

    For a transistor
    \[{{I}_{E}}={{I}_{B}}+{{I}_{C}}\]
    where    \[{{I}_{E}}=\] emitter current
    \[{{I}_{B}}=\] base current
    \[{{I}_{C}}=\] collector current
    and current gain \[\beta =\frac{\Delta {{I}_{C}}}{\Delta {{I}_{B}}}\]
    \[\Delta {{I}_{C}}=5\times {{10}^{-3}}\,A\]
    \[\Delta {{I}_{B}}=100\times {{10}^{-6}}\,A\]
    \[\beta =\frac{5}{100}\times 1000=50\]


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