All Free Electrical Engineering MCQs with Answers
Every Electrical Engineering question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
3,143 questions · page 96 of 158
- A. Linear devices only
- B. Digital devices only
- C. Both linear and digital devices
- D. None of the above
Explanation: IC technology is used in both linear applications, such as amplifiers, and digital applications, such as logic gates and processors.
Correct answer: Both linear and digital devices- A. Less space than
- B. More space than
- C. Same space as
- D. None of the above
Explanation: A transistor is fabricated as a small semiconductor junction structure, whereas an inductor requires a coil or magnetic structure that…
Correct answer: Less space than- A. Diode
- B. Transistor
- C. FET
- D. Capacitor
Explanation: Capacitors are most difficult to fabricate in an IC because useful capacitance requires relatively large chip area and carefully formed…
Correct answer: Capacitor- A. common source configuration
- B. common drain configuration
- C. common gate configuration
- D. none of the above
Explanation: The common-base BJT and common-gate JFET both keep the input-output common terminal at AC ground.
Correct answer: common gate configuration- A. drain to source current
- B. drain to source current with gate shorted
- C. drain to source current with gate open
- D. none of the above
Explanation: IDSS is the drain-to-source current when the gate is shorted to the source, so VGS equals zero.
Correct answer: drain to source current with gate shorted1906. A certain p-channel E-MOSFET has VGS(th) = -2V. If VGS= 0V, the drain current is ____________?
- A. 0 mA
- B. ID(on)
- C. maximum
- D. IDSS
Explanation: A p-channel enhancement MOSFET conducts only when VGS is sufficiently negative, below its negative threshold voltage.
Correct answer: 0 mA- A. 20 mA
- B. 0 mA
- C. 40 mA
- D. 10 mA
Explanation: A depletion MOSFET conducts at VGS = 0 V because its channel exists without gate bias.
Correct answer: 20 mA- A. at its widest point
- B. completely closed by the depletion region
- C. extremely narrow
- D. reverse baised
Explanation: At cutoff, the reverse-biased gate junction's depletion regions extend across the channel and stop majority-carrier flow.
Correct answer: completely closed by the depletion region- A. +4 V
- B. -4 V
- C. dependent on VGS
- D. data insufficient
Explanation: For the usual JFET convention, the pinch-off voltage Vp is the positive magnitude of the negative cutoff voltage: Vp = |VGS(off)| = 4 V.
Correct answer: +4 V- A. plate
- B. cathode
- C. grid
- D. none of the above
Explanation: The JFET source supplies or collects charge carriers, making it analogous to the cathode of a vacuum tube.
Correct answer: cathode- A. gate and drain
- B. drain and source
- C. gate and source
- D. input and output
Explanation: The conducting JFET channel provides the path through which drain current flows, so it lies between the drain and source terminals.
Correct answer: drain and source- A. pentode
- B. tetrode
- C. triode
- D. diode
Explanation: A JFET has a nearly constant-current region after pinch-off, where increasing drain voltage produces little additional current.
Correct answer: pentode- A. three
- B. four
- C. five
- D. two
Explanation: A JFET has a channel bordered by the gate on two sides, forming two gate-channel pn junctions.
Correct answer: two- A. cut off
- B. VDD
- C. VP
- D. V
Explanation: With VGS = 0, the JFET reaches pinch-off when VDS exceeds the pinch-off voltage VP, after which the drain current is approximately…
Correct answer: VP- A. of power rating
- B. the MOSFET has two gates
- C. the JFET has a pn junction
- D. none of the above
Explanation: A JFET controls its channel through a reverse-biased pn junction, whereas a MOSFET uses an insulated metal-oxide gate.
Correct answer: the JFET has a pn junction- A. 180o out of phase with the input
- B. in phase with the input
- C. 90o out of phase with the input
- D. taken at the source
Explanation: In a common-source amplifier, an increase in drain current produces a larger voltage drop across the drain resistor, making the drain…
Correct answer: 180o out of phase with the input- A. 2.05 V
- B. 25 V
- C. 0.5 V
- D. 1.89 V
Explanation: The effective drain load is 820 Ω || 10 kΩ ≈ 758 Ω, so Av ≈ gm(RD || RL) = 0.005 × 758 ≈ 3.79.
Correct answer: 1.89 V- A. 1
- B. 11.4
- C. 8.75
- D. 3.2
Explanation: Voltage gain is the ratio of output rms voltage to input rms voltage: Av = 3.2/0.280 ≈ 11.4. Therefore option b matches the calculated gain.
Correct answer: 11.4- A. the voltage gain will increase
- B. the transconductance will increase
- C. the voltage gain will decrease
- D. the Q-point will shift
Explanation: Removing the source bypass capacitor introduces source degeneration through the source resistor, reducing the AC voltage gain.
Correct answer: the voltage gain will decrease1920. If load resistance in the above question (Q.49) is removed, the output voltage will_____________?
- A. increase
- B. decrease
- C. stay the same
- D. be zero
Explanation: Removing the load makes the effective drain resistance larger because the external load is no longer in parallel with the drain resistor.
Correct answer: increase