MHT CET202526 Apr 2025Morning ShiftPhysicsSemiconductorsActual
In a common emitter transistor amplifier circuit, the input resistance is 1 8 ~K and output is obtained across a load resistance of 9 ~K . The alternating current gain is 70 . Corresponding to an a.c. input voltage of 6 mV , the output voltage will be
Options
- A0.7 V
- B1.4 V
- C2.1 V
- D4.2 V
Correct answer
C. 2.1 V
Step-by-step solution
The output voltage is determined by the voltage gain A_v = _ ac R_L R_ in , with R_ in = 1800 and R_L = 9000 . Substituting the given values, A_v = 70 9000 1800 = 350 . Thus, V_ out = A_v V_ in = 350 (6 10⁻³) = 2.1 V , which corresponds to option C .