Electronic Devices and Circuits – Multiple Choice Questions (MCQs)

1. 49. The characteristic curve of a BJT in common emitter configuration plots:

   • A. Ic vs Vce
   • B. Ib vs Vbe
   • C. Ic vs Ib
   • D. Vce vs Ib

2. 50. In a common source FET amplifier

   • A. the output voltage is usually ________ the input voltage.
   • B. In phase with
   • C. 180 degrees out of phase with
   • D. 90 degrees out of phase with

3. 51. The transconductance (gm) of a FET relates the change in drain current to the change in:

   • A. Gate voltage
   • B. Drain voltage
   • C. Source voltage
   • D. Body voltage

4. 52. Which type of transistor is preferred for high-frequency applications due to its lower input capacitance?

   • A. BJT
   • B. JFET
   • C. MOSFET
   • D. Both JFET and MOSFET

5. 53. The threshold voltage (Vt) of a MOSFET is the minimum Vgs required to:

   • A. Turn the device off
   • B. Turn the device on
   • C. Cause breakdown
   • D. Operate in saturation

6. 54. A Darlington pair configuration provides:

   • A. High voltage gain
   • B. High current gain
   • C. High input impedance
   • D. All of the above

7. 55. The purpose of a biasing circuit in a transistor amplifier is to:

   • A. Set the DC operating point
   • B. Provide AC gain
   • C. Filter noise
   • D. Match impedance

8. 56. Which component is used to limit the current in a series circuit?

   • A. Resistor
   • B. Capacitor
   • C. Inductor
   • D. Diode

9. 57. The form factor for a half-wave rectified sine wave is approximately:

   • A. 1.11
   • B. 1.57
   • C. 1.414
   • D. 1

10. 58. The form factor for a full-wave rectified sine wave is approximately:

    • A. 1.11
    • B. 1.57
    • C. 1.414
    • D. 1

11. 59. The ripple voltage in a filtered DC power supply decreases with:

    • A. Increase in load current
    • B. Decrease in filter capacitance
    • C. Increase in filter capacitance
    • D. Decrease in input frequency

12. 60. A rectifying diode allows current to flow easily in:

    • A. Both directions
    • B. One direction
    • C. Neither direction
    • D. Only at high frequencies