MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 1136 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics & Communication Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1051. |
Examine the circuit of figure and the following statements Vs is more than the zener breakdown voltage.IL = I1 - I2.Rs is less than zener nominal resistance. Which of the above statements are correct? |
| A. | 1, 2, 3 |
| B. | 1, 2 |
| C. | 1 only |
| D. | 2 and 3 |
| Answer» C. 1 only | |
| 1052. |
In figure, VEB = 0.6 V, β = 99. Then VC and IC are |
| A. | 9.3 V and 1.98 mA respectively |
| B. | 4.6 V and 1.98 mA respectively |
| C. | 9.3 V and 0.02 mA respectively |
| D. | 4.6 V and 0.02 mA respectively |
| Answer» B. 4.6 V and 1.98 mA respectively | |
| 1053. |
Which of the following statement about TRIAC is incorrect? |
| A. | It is not particularly suited to A.C. or mains power control |
| B. | Any one of its main terminals can be used either as cathode or as anode |
| C. | It can be triggered in response to both positive and negative gate terminals |
| D. | None of the above |
| Answer» B. Any one of its main terminals can be used either as cathode or as anode | |
| 1054. |
V MOS have the advantage of |
| A. | faster switching |
| B. | no thermal run away |
| C. | both (a) and (b) |
| D. | none of the above |
| Answer» D. none of the above | |
| 1055. |
IN 3242 is a |
| A. | P-N-P transistor |
| B. | N-P-N transistor |
| C. | UJT |
| D. | semi-conductor diode |
| Answer» E. | |
| 1056. |
For dc the current through coupling capacitor in CE amplifier circuit is |
| A. | very high |
| B. | high |
| C. | low |
| D. | zero |
| Answer» E. | |
| 1057. |
The semi-conductor type 2 N 34 indicates |
| A. | a n-channel MOSFET |
| B. | a JFET |
| C. | a diode with two electrodes |
| D. | a diode with three electrodes |
| Answer» D. a diode with three electrodes | |
| 1058. |
The gain of an FET amplifier can be changed by changing |
| A. | rm |
| B. | gm |
| C. | Rd |
| D. | none of the above |
| Answer» C. Rd | |
| 1059. |
In a Darlington pair |
| A. | the emitter of first transistor drives the base of the second |
| B. | the base of the first transistor drives the emitter of the second |
| C. | emitters of the two transistors are connected through a resistor |
| D. | none of the above |
| Answer» B. the base of the first transistor drives the emitter of the second | |
| 1060. |
CMOS is widely used in |
| A. | digital wrist watches |
| B. | analog circuits |
| C. | high power circuits |
| D. | all of the above |
| Answer» B. analog circuits | |
| 1061. |
A delay equalizer is a |
| A. | low pass filter |
| B. | band pass filter |
| C. | all pass filter |
| D. | high pass filter |
| Answer» C. all pass filter | |
| 1062. |
The signal input to a given amplifier is made up of 100 mΩ signal power and 1 mΩ noise power. The amplifier contributes an additional 100 mΩ of noise and has a power gain of 20 dB. The noise factor is |
| A. | 1 |
| B. | 1.5 |
| C. | 2 |
| D. | 15 |
| Answer» D. 15 | |
| 1063. |
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 | |
| 1064. |
In the circuit of figure β = 50 and VBE = 0.5 V. The quiescent value of base current IB is |
| A. | about 28 μA |
| B. | about 28 mA |
| C. | about 0.28 μA |
| D. | about 2.8 A |
| Answer» B. about 28 mA | |
| 1065. |
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 | |
| 1066. |
In the op-amp circuit of figure, V0 = |
| A. | Vi |
| B. | 3 Vi |
| C. | 5 Vi |
| D. | 0.5 Vi |
| Answer» D. 0.5 Vi | |
| 1067. |
Which of the following plot can be directly used to determine β? |
| A. | VCE versus iC for constant IB |
| B. | VBE versus iB for constant VCE |
| C. | VCB versus iC for constant IB |
| D. | All of the above |
| Answer» B. VBE versus iB for constant VCE | |
| 1068. |
An engineer designs an amplifier to have a voltage gain of 60, but when constructed it only had a gain of 50. Which of the following will increases from this type of operation? |
| A. | Stability |
| B. | Bandwidth |
| C. | Distortion |
| D. | Input resistance |
| Answer» D. Input resistance | |
| 1069. |
A Clapp's oscillator is |
| A. | a modified Hartley oscillator |
| B. | a modified Colpitt's oscillator |
| C. | a modified RC oscillator |
| D. | none of the above |
| Answer» C. a modified RC oscillator | |
| 1070. |
A negative feedback can be of |
| A. | 2 types |
| B. | 3 types |
| C. | 4 types |
| D. | only 1 type |
| Answer» D. only 1 type | |
| 1071. |
Consider the following statements : A clamper circuit adds or subtracts a dc voltage to a waveformdoes not change the waveformamplifiers the waveform Which are correct? |
| A. | 1, 2 |
| B. | 1, 3 |
| C. | 1, 2, 3 |
| D. | 2, 3 |
| Answer» B. 1, 3 | |
| 1072. |
In figure, current gain is |
| A. | a |
| B. | re |
| Answer» B. re | |
| 1073. |
Which of the following is non-sinusoidal oscillator? |
| A. | Multivibrator |
| B. | Relaxation oscillator using UJT |
| C. | Relaxation oscillator using tunnel diode |
| D. | Any of the above |
| Answer» B. Relaxation oscillator using UJT | |
| 1074. |
In figure v1 = 8 V and v2 = 4 V. Which diode will conduct? |
| A. | D2 only |
| B. | D1 only |
| C. | Both D1 and D2 |
| D. | Neither D1 nor D2 |
| Answer» C. Both D1 and D2 | |
| 1075. |
In CE approximately, the active region is where the collector curves are |
| A. | almost horizontal |
| B. | almost vertical |
| C. | inclined at 45° |
| D. | inclined at 60° |
| Answer» B. almost vertical | |
| 1076. |
Logarithmic amplifiers are used in |
| A. | adders |
| B. | dividers |
| C. | multipliers |
| D. | all of the above |
| Answer» C. multipliers | |
| 1077. |
The circuit of figure is called |
| A. | diode bias |
| B. | current mirror |
| C. | complementary mirror |
| D. | none of the above |
| Answer» D. none of the above | |
| 1078. |
In a transistor which of the following region is very lightly doped and is very thin? |
| A. | Emitter |
| B. | Base |
| C. | Collector |
| D. | None of the above |
| Answer» C. Collector | |
| 1079. |
One of the major applications of JFET is in |
| A. | switching |
| B. | constant current-source |
| C. | constant voltage-source |
| D. | electron flow regulation |
| Answer» B. constant current-source | |
| 1080. |
In full wave rectification, if the input frequency is 50 Hz, then frequency at the output of filter is |
| A. | 50 Hz |
| B. | 0 Hz |
| C. | 100 Hz |
| D. | 75 Hz |
| Answer» C. 100 Hz | |
| 1081. |
In a capacitor filter, the time constant RLC should be small. |
| A. | 1 |
| B. | |
| C. | 50 kHz |
| D. | 100 kHz |
| Answer» C. 50 kHz | |
| 1082. |
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 | |
| 1083. |
The common gate amplifier has a characteristically __________ input resistance and a __________ output resistance. |
| A. | low, low |
| B. | high, high |
| C. | low, high |
| D. | high, low |
| Answer» D. high, low | |
| 1084. |
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 Œ© and 16.7% | |
| 1085. |
Assertion (A): In the circuit shown figure the diode is used to protect the active devices. Transistor T goes into saturation when a positive pulse is applied at base and non conductingReason (R): When the current in an inductor is suddenly stopped, a high voltage is induced across it. |
| 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» B. Both A and R are correct but R is not correct explanation for A | |
| 1086. |
Which of the following contributes to harmonics distortion in amplifiers? |
| A. | Positive feedback |
| B. | Presence of noise |
| C. | Defective active device |
| D. | Non-linearity in active device |
| Answer» E. | |
| 1087. |
An amplifier has open loop gain of 100, input impedance 1 kΩ and output impedance 100 Ω. If negative feedback with β = 0.99 is used, the new input and output impedances are |
| A. | 10 Ω and 1 Ω |
| B. | 10 Ω and 10 kΩ |
| C. | 100 kΩ and 1 Ω |
| D. | 100 kΩ and 10 Ω |
| Answer» D. 100 kŒ© and 10 Œ© | |
| 1088. |
Symbol shown in figure represents a |
| A. | P-channel DEMOSFET |
| B. | N-channel DEMOSFET |
| C. | UJT with N-type base |
| D. | UJT with P-type base |
| Answer» D. UJT with P-type base | |
| 1089. |
The circuit in the given figure is |
| A. | low pass filter |
| B. | high pass filter |
| C. | band Pass filter |
| D. | band reject filter |
| Answer» B. high pass filter | |
| 1090. |
The voltage gains of an amplifier without feedback and with negative feedback respectively are 100 and 20. The percentage of negative feedback would be. |
| A. | 0.4 |
| B. | 0.05 |
| C. | 0.2 |
| D. | 0.8 |
| Answer» D. 0.8 | |
| 1091. |
The most widely used LC oscillator is |
| A. | Hartley oscillator |
| B. | Crystal oscillator |
| C. | Colpitt's oscillator |
| D. | Clapp's oscillator |
| Answer» B. Crystal oscillator | |
| 1092. |
The phase angle of lead circuit is |
| A. | between 0 and -90° |
| B. | between 0 and +90° |
| C. | 90° |
| D. | more than 90° |
| Answer» C. 90¬∞ | |
| 1093. |
A ripple in collector supply voltage of the output stage of amplifier causes noise. |
| A. | 1 |
| B. | |
| C. | 100 μA |
| D. | 25 μA |
| Answer» B. | |
| 1094. |
Tuned amplifiers are used at radio frequencies. |
| A. | 1 |
| B. | |
| C. | 0.3 V and 0.7 V |
| D. | 0.7 V and 0.3 V |
| Answer» B. | |
| 1095. |
In a CE amplifier circuit, the output voltage |
| A. | is very small |
| B. | is always constant |
| C. | depends on β |
| D. | none of the above |
| Answer» D. none of the above | |
| 1096. |
In figure, transistor βdc = 100 and LED voltage when it is conducting is 2 V. Then the base current which saturates the transistor is |
| A. | 18 mA |
| B. | 1.8 mA |
| C. | 0.18 mA |
| D. | 0.018 mA |
| Answer» D. 0.018 mA | |
| 1097. |
In a biased limiter the clipping level can be adjusted by adjusting the voltage of battery. |
| A. | 1 |
| B. | |
| C. | sinusoidal |
| D. | full rectified sinusoidal |
| Answer» B. | |
| 1098. |
Study the circuit of figure and examine the following statements It is an active low pass finer.It is a second order filter.The change in gain is 40 dB/decade. Which of the above statements are correct? |
| A. | 1, 2 and 3 |
| B. | 1 and 2 |
| C. | 1 and 3 |
| D. | 2 and 3 |
| Answer» B. 1 and 2 | |
| 1099. |
An amplifier with loop gain Aβ will be more stable for value of Aβ as |
| A. | 0.95 |
| B. | 0.7 |
| C. | 1.2 |
| D. | 1.5 |
| Answer» C. 1.2 | |
| 1100. |
Which of the following can be used to isolate a low impedance from a high impedance source? |
| A. | Emitter follower |
| B. | p filter |
| C. | Darlington pair |
| D. | Any of the above |
| Answer» D. Any of the above | |