Negative feedback in an amplifier____________?

Related Mcqs:

1. An amplifier without feedback has a voltage gain of 50,input resistance os 1 KΩ & Output resistance of 2.5KΩ.The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is___________?

   A. 1/11KΩ
   B. 1/5KΩ
   C. 5KΩ
   D. 11KΩ

2. Voltage Series feedback also called series-shunt feedback) results in__________?

   A. Increase in both input & output impedances
   B. Decreases in both input & output impedances
   C. Increase in input impedance & decreases in output impedance
   D. Decrease in input impedance & increase in output impedance

3. The bandwidth of an RF tuned amplifier is dependent on____________?

   A. Q –factor of the tuned o/p circuit
   B. Q –factor of the tuned i/p circuit
   C. Quiescent operating point
   D. Q-factor of the o/p and i/p circuits as well as quiescent operating point

4. Thermal runaway is not possible in FET because as the temperature of FET increases_________________?

   A. the mobility decreases
   B. the transconductance increases
   C. the drain current increases
   D. none of the above

5. Most of the linear ICs are based on the two-transistor differential amplifier because of its___________?

   A. input voltage dependent linear transfer characteristic
   B. high voltage gain
   C. high input resistance
   D. high CMRR

6. An OPAMP has a slew rate of 5 V/μ S .The largest sine wave O/P voltage possible at a frequency of 1 MHZ is [Hint: Slew rate is defined as the max. rate of change of output voltage. Its unit is V/μS.

   A. 10 volts
   B. 5 volts
   C. 5/1 volts
   D. 5/2 volts

7. The early effect in a bipolar junction transistor is caused by_______________?

   A. fast turn-on
   B. fast turn-off
   C. large collector-base reverse bias
   D. large emitter-base forward bias

8. Generally, the gain of a transistor amplifier falls at high frequencies due to the___________?

   A. Internal Capacitance of the device
   B. Coupling capacitor at the input
   C. Skin effect
   D. Coupling capacitor at the output

9. The horizontal intercept of dc load line is the same as ideal____________?

   A. cut off point
   B. saturation point
   C. operating point
   D. quasi saturation point

10. An npn BJT has gm=38mA/v, cµ =10¯14 F, cπ =10¯13F and DC current gain β0=90.For this transistor fT & fβ are________?

    A. fT =1.64 x 108 Hz & fβ = 1.47 x 1010 Hz.
    B. fT =1.47 x 1010 Hz & fβ = 1.64 x 108 Hz
    C. fT =1.33 x 1012 Hz & fβ = 1.47 x 1010 Hz
    D. fT =1.47 x 1010 Hz & fβ = 1.33 x 1012 Hz