Explore topic-wise MCQs in Engineering.

This section includes 9294 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.

2301.

In figure, VG =

A. 2.22 V
B. 22.2 V
C. 0.22 V
D. 0.022 V
Answer» B. 22.2 V
Discussion
2302.

A diode can have a very high forward resistance.

A. True
B. False
Answer» C.
Discussion
2303.

If an amplifier with gain of - 100 and feedback of = - 0.1 has a gain change of 20% due to temperature the change in gain of the feedback amplifier will be

A. 0.02%
B. 2%
C. 0.1%
D. 0.01%
Answer» C. 0.1%
Discussion
2304.

In figure the cut in voltage of diode is 0.7 V and its bulk resistance is 20 Ω. The peak value of circuit current of during positive and negative half cycles are

A. 10 mA and zero
B. 9.12 mA and zero
C. 9.3 mA and zero
D. zero and 9.12 mA
Answer» C. 9.3 mA and zero
Discussion
2305.

A voltage gain of a CE amplifier connected in collector to base configuration is 50. Collector to base resistor RF = 1 kΩ, RC = 4Ω, the O/P resistance R0 =?

A. 800 Ω
B. 813 Ω
C. 817 Ω
D. 819 Ω
Answer» C. 817 Ω
Discussion
2306.

A voltage multiplier circuit, using diodes and capacitors is suitable for

A. high voltage high current device
B. high voltage low current device
C. low voltage low current device
D. low voltage high current device
Answer» C. low voltage low current device
Discussion
2307.

In a CE amplifier the ac emitter resistance

A. is zero
B. is high
C. is very high
D. may have any value
Answer» B. is high
Discussion
2308.

To bypass a 100 ohm emitter resistor at

A. 10 F
B. 100 F
C. 1000 F
D. 1 F
Answer» D. 1 F
Discussion
2309.

In a CE amplifier the dc load line is the same as ac load line when

A. ac collector resistance and dc collector resistance are equal
B. ac collector resistance and dc emitter resistance are equal
C. ac collector resistance is very high
D. ac collector resistance is one half of dc collector resistance
Answer» D. ac collector resistance is one half of dc collector resistance
Discussion
2310.

If the output current wave shape of class C circuit has a period of 1 s and a pulse width of 0.006 s, the duty cycle is

A. 6%
B. 0.6%
C. 0.006%
D. 0.06%
Answer» C. 0.006%
Discussion
2311.

Which configuration is suitable for impedance matching?

A. CB
B. CE
C. CC
D. CB and CE
Answer» D. CB and CE
Discussion
2312.

A BJT is said to be operating in saturation region if

A. both junctions are reverse biased
B. both junctions are forward biased
C. base emitter junction is forward biased and base collector junction is reverse biased
D. base collector junction is forward biased and base emitter junction is reverse biased
Answer» C. base emitter junction is forward biased and base collector junction is reverse biased
Discussion
2313.

A class C amplifier has input frequency of 200 kHz. If width of collector pulses is 0.1 s, duty cycle is

A. 1%
B. 2%
C. 10%
D. 20%
Answer» C. 10%
Discussion
2314.

In a transistor the minimum and maximum values of dc are 100 and 121. The proper value of dc to be used to locate Q point is

A. 100
B. 121
C. 110.5
D. 110
Answer» E.
Discussion
2315.

Output of a phase splitter is

A. a pair of sine waves of unequal amplitude
B. a pair of sine waves of equal amplitudes
C. a pair of sine waves of equal amplitudes and opposite phase
D. a pair of sine waves of unequal amplitudes and opposite phase
Answer» D. a pair of sine waves of unequal amplitudes and opposite phase
Discussion
2316.

FET amplifier is more difficult to analyse than BJT amplifier.

A. True
B. False
Answer» C.
Discussion
2317.

The input to an op-amp integrating amplifier is a constant voltage. The output will be

A. a constant voltage
B. a sawtooth wave
C. a ramp
D. ac voltage
Answer» E.
Discussion
2318.

A dc power supply has no load voltage of 30 V and full load voltage of 25 V at full load current of 1 A. The output resistance and voltage regulation respectively are

A. 5 Ω and 25%
B. 25 Ω and 20%
C. 5 Ω and 16.7%
D. 25 Ω and 16.7%
Answer» C. 5 Ω and 16.7%
Discussion
2319.

The main advantage of CC amplifier is

A. High input impedance and low output impedance
B. Low input impedance and high output impedance
C. High voltage gain
D. High current gain
Answer» B. Low input impedance and high output impedance
Discussion
2320.

If a = 0.995, IE = 10 mA, ICO = 0.5 mA, then ICEO will be

A. 100 A
B. 25 A
C. 10.1 A
D. 10.5 A
Answer» B. 25 A
Discussion
2321.

Assertion (A): In class C amplifier the efficiency is more than that for other classes of amplifiersReason (R): In class C amplifier we can get high efficiency over a wideband

A. Both A and R are correct and R is correct explanation for A
B. Both A and R are correct but R is not correct explanation for A
C. A is correct R is wrong
D. A is wrong R is correct
Answer» D. A is wrong R is correct
Discussion
2322.

In the following figure C = 0.02 F, and Vth is known to be of frequency = 107 rad/sec and rd = 2.5 Ω and ZTh = RTh = 10 Ω Then phase angle between id and Vd

A. 26.5
B. 25
C. 30
D. 0
Answer» B. 25
Discussion
2323.

Regulation of the DC power supply of 12 V, 100 mA is the effective resistance of power supply is 20 Ω

A. 22%
B. 131%
C. 30%
D. 20%
Answer» E.
Discussion
2324.

A bridge diode circuit using ideal diodes has in input voltage of 20 sin t volts. The average and rms values of output voltage are

A. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/317-229-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/317-229-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/317-229-3.png">
D. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/317-229-4.png">
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/317-229-2.png">
Discussion
2325.

An increase in ambient temperature means that maximum power rating of transistor

A. will increase
B. will decrease
C. may increase or decrease
D. may increase or remain the same
Answer» C. may increase or decrease
Discussion
2326.

Two CE stages are coupled through a capacitor. To calculate the quiescent base current of the two transistors, the capacitor is treated as

A. open circuit
B. short circuit
C. neither (a) nor (b)
D. either (a) or (b)
Answer» B. short circuit
Discussion
2327.

If it is desired to have low output impedance in an amplifier circuit then we should use

A. common collector circuit
B. common base circuit
C. common emitter circuit
D. either (b) or (c)
Answer» B. common base circuit
Discussion
2328.

Generally the gain of a transistor amplifier falls at high frequencies due to the

A. internal capacitance of device
B. coupling capacitor at the I/P
C. skin effect
D. coupling capacitor at the O/P
Answer» B. coupling capacitor at the I/P
Discussion
2329.

A CE amplifier has re = 6 &amp;ohm;, = 100 and a = 0.98. The input impedance is

A. 6 &ohm;
B. 100 &ohm;
C. 600 &ohm;
D. 98 &ohm;
Answer» D. 98 &ohm;
Discussion
2330.

A full wave diode rectifier using centre tapped transformer has diodes with forward resistance of 50 ohms each. The load resistance of 50 ohms each. The load resistance is also 50 ohms. The voltage regulation is

A. 20%
B. 50%
C. 100%
D. 200%
Answer» D. 200%
Discussion
2331.

Leakage current approximately doubles for every 10 C increase in the temperature of a transistor has ICBO = 400 nA at 25 C, then its leakage current at 80 C

A. 10 A
B. 18 A
C. 20 A
D. 15 A
Answer» C. 20 A
Discussion
2332.

Values of VT at 20 C for an ideal P-N diode

A. 25.27 mV
B. 30.3 mV
C. 23 mV
D. 50 mV
Answer» B. 30.3 mV
Discussion
2333.

For the amplifier circuit of figure, the h parameters of transistor are hib = 25 &amp;ohm;, hfb = 0.999, hob = 10-6 &amp;ohm;. The voltage gain is

A. 0.999
B. 1.98
C. 20
D. 400
Answer» E.
Discussion
2334.

In figure, VCC = + 30 V, R1 = 200 k&amp;ohm; and R2 = 100 k&amp;ohm;. If VBE = 0.7 V, the voltage a cross RE =

A. +20 V
B. +19.3 V
C. +10 V
D. +9.3 V
Answer» E.
Discussion
2335.

A CB amplifier has IE = 3.5 mA, a = 0.98 and RL = 600 &amp;ohm;. The input impedance

A. 0.98 &ohm;
B. 0.025 &ohm;
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/322-317-1.png">
D. 600 &ohm;
Answer» D. 600 &ohm;
Discussion
2336.

In the circuit figure LED will be on when v1 is

A. less than 6 V
B. more than 6 V
C. less than 12 V
D. more than 12 V
Answer» C. less than 12 V
Discussion
2337.

The most commonly used bias in BJT amplifier circuits is

A. voltage divider bias
B. emitter bias
C. collector bias
D. collector feedback bias
Answer» B. emitter bias
Discussion
2338.

In the circuit of figure the diode

A. will conduct as the whole cycle
B. will conduct in the positive half cycle
C. will not conduct
D. will conduct from 30 to 150 in the positive half cycle
Answer» D. will conduct from 30 to 150 in the positive half cycle
Discussion
2339.

A differential amplifier consists of two CB amplifiers.

A. True
B. False
Answer» C.
Discussion
2340.

Figure shows a portion of linear v - i characteristics of diode. If applied voltage is + 6 V, the current will be

A. 42 mA
B. 48 mA
C. 51 mA
D. 54 mA
Answer» E.
Discussion
2341.

A power transistor dissipates 5 W. If ambient temperature is 30 and case to air thermal resistance is 10 C/W, the case temperature is

A. 80 C
B. 20 C
C. 32 C
D. 305 C
Answer» B. 20 C
Discussion
2342.

An R-C coupled amplifier has mid-frequency gain of 200 and a frequency response from 100 Hz to 20 kHz. A negative feedback network with = 0.2 is incorporated into the amplifier circuit, the Bandwidth will be

A. 50 kHz
B. 20 kHz
C. 100 kHz
D. infinite
Answer» D. infinite
Discussion
2343.

In a transistor E mode the collector current with the transistor in cut off region is

A. zero
B. high
C. equal to saturated value
D. none of the above
Answer» B. high
Discussion
2344.

Which of the following?

A. Voltage series feedback and decrease I/P impedance.
B. Voltage shunt feedback and decrease I/P impedance.
C. Voltage series feedback and increase I/P impedance.
D. Voltage shunt feedback and increase I/P impedance.
Answer» D. Voltage shunt feedback and increase I/P impedance.
Discussion
2345.

In a transistor CE mode, VCC = +30 V. If the transistor is in cut off region, VCE =

A. +30 V
B. +20 V
C. 10 V
D. zero
Answer» B. +20 V
Discussion
2346.

The dc load current in a bridge rectifier circuit is 10 mA. The dc load current through each diode is

A. 40 mA
B. 20 mA
C. 10 mA
D. 5 mA
Answer» E.
Discussion
2347.

Two CE stages, 1 and 2 are coupled through a capacitor. VCC is the same for both. Base resistances RB1 and RB2 are such that RB1 &gt; RB2. Then

A. base currents for both stages are equal
B. base current of stage 1 is more than that of stage 2
C. base current of stage 2 is more than that of stage 1
D. either (b) or (c)
Answer» D. either (b) or (c)
Discussion
2348.

In a two stage CE amplifier circuit, the ac collector resistance of the first stage depends on

A. load resistance
B. input impedance of first stage
C. input impedance of second stage
D. all of the above
Answer» D. all of the above
Discussion
2349.

In a CE amplifier the ac cut off voltage is 9 V and slope of ac load line is - 0.5 mA/V. The ac saturation current is

A. 9 mA
B. 4.5 mA
C. 3 mA
D. 18 mA
Answer» C. 3 mA
Discussion
2350.

An integrating amplifier has resistance in feedback path.

A. True
B. False
Answer» C.
Discussion