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.

1701.

An op-amp uses

A. RC coupling
B. direct coupling
C. transformer coupling
D. either (b) or (c)
Answer» C. transformer coupling
Discussion
1702.

The ripple factor of a power supply is

A. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/326-419-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/326-419-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/326-419-3.png">
D. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/326-419-4.png">
Answer» C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/326-419-3.png">
Discussion
1703.

In a P-N-P junction transistor as compared to base region is more heavily doped so that

A. leakage current is minimized
B. recombination will be increased in the base region
C. the flow across the base regional is only because of electrons
D. the flow across the base region is mainly because of holes
Answer» E.
Discussion
1704.

The input resistance R, of an ideal voltage amplifier is __________ and that of a current amplifier is __________ .

A. zero, zero
B. infinite, infinite
C. zero, infinite
D. infinite, zero
Answer» E.
Discussion
1705.

In every practical oscillator the loop gain is slightly more than unit and amplitude of oscillations is limited by

A. magnitude of loop gain
B. onset of non-linearity
C. magnitude of gain
D.
Answer» C. magnitude of gain
Discussion
1706.

When the emitter current of a transistor is changed by 1 mA, its collector current changes by 0.990 mA. The common base short circuit current gain a for the transistor is

A. 0.99
B. 1.01
C. 1.001
D. 0.990
Answer» B. 1.01
Discussion
1707.

A major advantage of TWT over a Klystron lies in its

A. higher bandwidth
B. higher gain
C. higher frequency
D. higher output
Answer» C. higher frequency
Discussion
1708.

The heat sink disposes off heat mainly by

A. radiation
B. natural convection
C. forced convection
D. conduction
Answer» C. forced convection
Discussion
1709.

In CE amplifier circuit, voltage gain is directly proportional to

A.
B. collector supply voltage
C. base resistance
D. none of the above
Answer» B. collector supply voltage
Discussion
1710.

The main disadvantage of a JFET is

A. low gain-bandwidth product
B. high noise level
C. high cost
D. low gain
Answer» B. high noise level
Discussion
1711.

A clamper

A. adds a dc component to the input signal
B. removes signal voltages above or below a specified value
C. both (a) and (b)
D. either (a) or (b)
Answer» D. either (a) or (b)
Discussion
1712.

For holding the drain current constant in spite of large changes in JFET parameters

A. current source bias is used
B. voltage divider bias is used
C. reverse bias is used
D. no bias is used
Answer» B. voltage divider bias is used
Discussion
1713.

For Q &gt;&gt; 1, the output frequency of LC oscillator is equal to resonant frequency.

A. True
B. False
Answer» B. False
Discussion
1714.

At the peak of negative half cycle in figure

A. diode A is forward biased and diode B is reverse biased
B. both diodes are reverse biased
C. both diodes are forward biased
D. diode A is reverse biased and diode B is forward biased
Answer» E.
Discussion
1715.

In a CE amplifier the Q point is very close to cutoff point on the load line. This results in

A. saturation clipping
B. cut off clipping
C. both saturation and cut off clipping
D. either saturation clipping or cut off clipping
Answer» C. both saturation and cut off clipping
Discussion
1716.

If a transistor is operating with both of its Junctions forward biased, but with the collector base forward biased, but with the collector base forward bias greater than the emitter-base forward bias, then it is operating in the

A. forward active mode
B. reverse saturation mode
C. reverse active mode
D. forward saturation mode
Answer» D. forward saturation mode
Discussion
1717.

An inverting voltage feedback is a

A. voltage amplifier
B. current amplifier
C. current to voltage converter
D. voltage to current converter
Answer» D. voltage to current converter
Discussion
1718.

The resolution of 4 bit counting ADC is 0.5 volt, for an Analog input of 6.6 volts. The digital output of ADC will be

A. 1011
B. 1101
C. 1100
D. 1110
Answer» C. 1100
Discussion
1719.

The circuit in the figure is has two CMOS-NOR gates. This circuit functions as a

A. flip-flop
B. schmitt trigger
C. monostable multivibrator
D. astable multivibrator
Answer» D. astable multivibrator
Discussion
1720.

ALU carries out

A. arithmetic operations
B. logic operations
C. both arithmetic and logic operations
D. none of the above
Answer» D. none of the above
Discussion
1721.

Fastest memory cell

A. bubble memory
B. core memory
C. semiconductor memory
D. superconductor memory
Answer» D. superconductor memory
Discussion
1722.

A mod-2 counter followed by a mod 5 is same as

A. mod-7 counter
B. A decade counter
C. mod-3 counter
D. none
Answer» C. mod-3 counter
Discussion
1723.

The values of 25 in octal system is

A. 40
B. 20
C. 400
D. 200
Answer» B. 20
Discussion
1724.

When the emitter current of a transistor is changed by 1 mA, its collector current changes by 0.990 mA. The common-emitter short-circuit current gain is

A. 1
B. 199
C. 99
D. 9.9
Answer» D. 9.9
Discussion
1725.

In figure Vi may vary from 15 to 20 V and load current may vary from 20 mA to 100 mA. Suitable maximum value of R is

A. 20 &ohm;
B. 50 &ohm;
C. 100 &ohm;
D. 200 &ohm;
Answer» C. 100 &ohm;
Discussion
1726.

In a transistor amplifier, the reverse saturation current ICO

A. Doubles for every 10 C rise in temperature
B. Doubles for every 20 C rise in temperature
C. Increase 100 C with temperature
D. Doubles for every 5 C rise in temperature
Answer» B. Doubles for every 20 C rise in temperature
Discussion
1727.

Assertion (A): A common collector amplifier is used for matching a high impedance source to a low impedance loadReason (R): A common collector amplifier has a near unity voltage gain

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» C. A is correct R is wrong
Discussion
1728.

Pick the odd-one out

A. Hartley Oscillator
B. Colpitt oscillator
C. Clapp oscillator
D. Weinbridge oscillator
Answer» E.
Discussion
1729.

In a CE amplifier the output coupling capacitor is short circuited. The dc collector voltage

A. will increase
B. may increase or decrease
C. will remain the same
D. will decrease
Answer» E.
Discussion
1730.

A certain transistor has adc of 0.98 and a collectors leakage current of 5 A. If IE = 1 mA, the collector current will be

A. 1.005 mA
B. 0.985 mA
C. 0.975 mA
D. 0.955 mA
Answer» C. 0.975 mA
Discussion
1731.

If 1.5% of the output of an amplifier is feedback positively to the input, the minimum gain required of the amplifier for oscillations to occur, is

A. 16.6
B. 44.4
C. 66.6
D. 75
Answer» D. 75
Discussion
1732.

The use of a capacitor filter in a rectifier circuit gives satisfactory performance only when the load

A. current is high
B. current is low
C. voltage is high
D. voltage is low
Answer» C. voltage is high
Discussion
1733.

Which of the following amplifier circuits has highest input impedance?

A. Circuit using BJT
B. Circuit using JFET
C. Circuit using MOSFET
D. Either (a) or (b)
Answer» D. Either (a) or (b)
Discussion
1734.

In a CE amplifier the Q point is very close to saturation point on the dc load line. This results in

A. positive clipping of collector current
B. negative clipping of collector current
C. both positive and negative clipping of collector current
D. either positive or negative clipping of collector current
Answer» B. negative clipping of collector current
Discussion
1735.

Class-B amplifier has less efficiency compared to

A. class A
B. class B
C. class C
D. class A, AB and C
Answer» B. class B
Discussion
1736.

In the amplifier circuit figure the quiescent point voltage and current are

A. 12 V, 5 mA
B. 12 V, 2 mA
C. 10 V, 2 mA
D. 10 V, 5 mA
Answer» D. 10 V, 5 mA
Discussion
1737.

For a BJT, and a are related as

A. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/331-495-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/331-495-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/331-495-3.png">
D. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/331-495-4.png">
Answer» E.
Discussion
1738.

Calculate the O/P voltage of a non-inverting constant gain multiplier with R1 = 100 k&amp;ohm;, Rf= 600 k&amp;ohm;, V1 = 2 volt, then O/P voltage Vo of non inverting op-amp is given by

A. 16 V
B. 14 V
C. 20 V
D. 15 V
Answer» C. 20 V
Discussion
1739.

In a rectifier only a portion of input power is converted into DC power. The rest is AC power.

A. True
B. False
Answer» B. False
Discussion
1740.

The slope of the transfer characteristics of an N-channel JFET is

A. positive
B. negative
C. constantly varying
D. zero
Answer» C. constantly varying
Discussion
1741.

In a JFET, gates are always

A. forward biased
B. reverse biased
C. either forward or reverse biased
D. unbiased
Answer» C. either forward or reverse biased
Discussion
1742.

By connecting external resistances to a differential amplifier we can adjust

A. voltage gain
B. bandwidth
C. both voltage gain and bandwidth
D. none of the above
Answer» D. none of the above
Discussion
1743.

CMRR of an op-amp is about 0.1.

A. True
B. False
Answer» C.
Discussion
1744.

In the circuit of figure for sinusoidal input the waveform of the output will be as shown in

A. figure A
B. figure B
C. figure C
D. figure D
Answer» E.
Discussion
1745.

An engineer designs an amplifier to have a voltage gain of 60, but when constructed it only had a gain of 50. What value of feedback will double the gain?

A. +0.5%
B. +0.66%
C. +1%
D. +3.3%
Answer» D. +3.3%
Discussion
1746.

CMRR is the ratio of differential voltage gain to common mode gain.

A. True
B. False
Answer» B. False
Discussion
1747.

The purpose of impedance matching in an amplifier circuit is to achieve

A. high efficiency
B. reduce distortion
C. maximum power transfer
D. none of the above
Answer» D. none of the above
Discussion
1748.

The maximum theoretical efficiency for class A amplifier is

A. 12.5%
B. 25%
C. 50%
D. 75%
Answer» C. 50%
Discussion
1749.

In a BJT CE amplifier circuit the value of coupling capacitor should be such that

A. its reactance is small for the lowest frequency in the input and output
B. its reactance is high for the lowest frequency in the input and output
C. its reactance is zero for the lowest frequency in the input and output
D. its reactance is infinite for the lowest frequency in the input and output
Answer» B. its reactance is high for the lowest frequency in the input and output
Discussion
1750.

In order to rectify sinusoidal signals of millivolt range (&lt; 0.6 V)

A. bridge rectifier using diodes can be employed
B. full wave diode rectifier can be used
C. a diode is to be inserted in the feedback loop of an op-amp
D. a diode is to be inserted in the I/P of an op-amp
Answer» D. a diode is to be inserted in the I/P of an op-amp
Discussion