MHT CET202617 April 2026Evening ShiftPhysicsSemiconductorsActual
In common emitter configuration of transistor amplifier, r_i , R_L and represent the input resistance, load resistance and the a.c. current gain respectively. The voltage gain A_V and power gain A_P are represented in magnitude respectively by
Options
- A( r_i R_L ) , ^2 ( r_i R_L )
- B( R_L r_i ) , ( R_L r_i )^2
- C( R_L r_i ) , ^2 ( R_L r_i )
- D( r_i R_L ) , ( r_i R_L )^2
Correct answer
C. ( R_L r_i ) , ^2 ( R_L r_i )
Step-by-step solution
Voltage gain A_V is the ratio of output voltage to input voltage. A_V = V_ out V_ in = I_ out R_L I_ in r_i Since the a.c. current gain is = I_ out I_ in , A_V = ( R_L r_i ) Power gain A_P is the ratio of output power to input power. A_P = P_ out P_ in = I_ out ^2 R_L I_ in ^2 r_i A_P = ( I_ out I_ in )^2 ( R_L r_i ) = ^2 ( R_L r_i ) Answer: ( R_L r_i ) , ^2 ( R_L r_i )