MCQOPTIONS
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MCQOPTIONS
This section includes 1800 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.
| 1001. |
In drawing phasor diagrams, RMS values are used. |
| A. | 1 |
| B. | |
| C. | [y] = [ya] [yb] |
| D. | [y] = [ya] + [yb] |
| Answer» B. | |
| 1002. |
The value of the inductance of coil in which a current increases linearly from zero to 0.1A in 0.2 second producing a voltage of 5 volts is __________ . |
| A. | 2.5 |
| B. | 5 |
| C. | 10 |
| D. | 20 |
| Answer» D. 20 | |
| 1003. |
In h parameter representation, the independent variables are |
| A. | I1 and V2 |
| B. | I2 and V1 |
| C. | V1 and V2 |
| D. | I1 and I2 |
| Answer» B. I2 and V1 | |
| 1004. |
In ZRC (s) = 0 at s =‚àû, the last element in second Foster realization will be |
| A. | R |
| B. | C |
| C. | R and C in series |
| D. | R and C in parallel |
| Answer» C. R and C in series | |
| 1005. |
A network is said to be two port network if there is no independent source in the networkno dependent source in the networknon-linear component in the circuitno external connection exist between I/P and 0/P |
| A. | 1, 2, 3 |
| B. | 3, 4, 2 |
| C. | 1, 3, 4 |
| D. | 4, 3, 1, 2 |
| Answer» D. 4, 3, 1, 2 | |
| 1006. |
The relative permeability of an iron specimen is 400 when B = 0.2 T. If B = 0.4 T, μr will be |
| A. | 400 |
| B. | less than 400 |
| C. | more than 400 |
| D. | more or less than 400 |
| Answer» E. | |
| 1007. |
If f1 and f2 and half-power frequency and f0 be resonant frequency, the selectivity of R-L-C series circuit is given by |
| A. | (f2 - f1)/2f0 |
| B. | (f2 - f1)/f0 |
| C. | (f2 - f0)/(f1 - f0) |
| D. | (f2 - f1)/(f1 - f0) |
| Answer» C. (f2 - f0)/(f1 - f0) | |
| 1008. |
A series RLC circuit has Q = 5. A voltage of 10 V rms is applied to it. At resonance, the voltage across C is |
| A. | 10 V rms |
| B. | 10 V peak |
| C. | 50 V rms |
| D. | 50 V peak |
| Answer» D. 50 V peak | |
| 1009. |
When sources of different frequencies feed a network the only method of solution is superposition theorem. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1010. |
The inductance of a coil can be increased by |
| A. | choosing core material having high relative permeability |
| B. | decreasing diameter of the former |
| C. | decreasing the number of turns |
| D. | increasing core length |
| Answer» B. decreasing diameter of the former | |
| 1011. |
At very low temperatures, semiconducting materials behave as insulators. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1012. |
Pico-farad is equal to |
| A. | 10-6 farad |
| B. | 10-12 farad |
| C. | 10-3 farad |
| D. | 10-9 farad |
| Answer» C. 10-3 farad | |
| 1013. |
For an RC driving point impedance function, the poles and zeros |
| A. | should alternate on real axis |
| B. | should alternate only on negative real axis |
| C. | should alternate on imaginary axis |
| D. | none of the above |
| Answer» B. should alternate only on negative real axis | |
| 1014. |
In the network of figure, the voltage drops across R1, R2, R3 are 6 V, 8 V and 12 V with polarities as shown. The value of R3 is |
| A. | 12 Ω |
| B. | 8 Ω |
| C. | 5 Ω |
| D. | 3 Ω |
| Answer» E. | |
| 1015. |
In an unloaded transformer, the fluxes limiting the primary and secondary are 30 mWb and 20 mWb. The coefficient of coupling is |
| A. | 1 |
| B. | 0.1 |
| C. | 0.33 |
| D. | 0.67 |
| Answer» E. | |
| 1016. |
A 2-terminal network consists of one of the RLC elements. The elements is connected to an ac supply. The current through the element is 1 A. When an inductor is inserted in series between the source and the element, the current through the element becomes 2 A. What is this element? |
| A. | A resistor |
| B. | An inductor |
| C. | A capacitor |
| D. | Cannot be single element |
| Answer» D. Cannot be single element | |
| 1017. |
The units of resistivity are ohm-metre. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1018. |
The average value of wave in figure is |
| A. | 90 V |
| B. | 75 V |
| C. | 60 V |
| D. | 50 V |
| Answer» C. 60 V | |
| 1019. |
In figure, capacitor is uncharged. The switch is closed at t = 0 at t = 0+ di/dt is |
| A. | 100 A/s |
| B. | -100 A/s |
| C. | 1000 A/s |
| D. | -1000 A/s |
| Answer» C. 1000 A/s | |
| 1020. |
A voltage v = 100 sin (100 pt + 45°) V is applied to an impedance 10 + j10 ohm. The current is |
| A. | 10 ∠45° A |
| B. | 7.07 ∠45° A |
| C. | 5 ∠45° A |
| D. | 5 ∠0 A |
| Answer» E. | |
| 1021. |
A circuit said to be lumped when physical dimensions of all the component are __________ . |
| A. | greater compared with wavelength of electromagnetic signal |
| B. | small compared with wavelength electromagnetic signal |
| C. | negligible compared with wavelength of electromagnetic signal |
| D. | equal compared with wavelength of electromagnetic signal |
| Answer» D. equal compared with wavelength of electromagnetic signal | |
| 1022. |
The Kirchoff's laws fail in which of the following circuits? |
| A. | Linear circuits |
| B. | Non-linear circuits |
| C. | Lumped parameters circuits |
| D. | Distributed parameters circuits |
| Answer» E. | |
| 1023. |
In figure, the effective resistance across AB is |
| A. | R |
| B. | R - 1 |
| C. | R/2 |
| Answer» D. | |
| 1024. |
Consider the following statements Tellegen's theorem is applicable to any lumped network.Reciprocity theorem is applicable to linear bilateral network.Thevenin theorem is applicable to two terminal linear active network.Norton's theorem is applicable to linear active network. Which of the above statements are correct? |
| A. | 1, 2 and 3 |
| B. | 1, 2, 3 and 4 |
| C. | 1, 2 and 4 |
| D. | 3 and 4 |
| Answer» C. 1, 2 and 4 | |
| 1025. |
Nichrome is commonly used for |
| A. | lamp filaments |
| B. | transformer winding |
| C. | heater coils |
| D. | battery connections |
| Answer» D. battery connections | |
| 1026. |
Damping ratio = |
| A. | actual resistance/critical resistance |
| B. | critical resistance/actual resistance |
| C. | critical resistance |
| D. | none of the above |
| Answer» B. critical resistance/actual resistance | |
| 1027. |
A non-linear element has zero resistance. |
| A. | 1 |
| B. | |
| Answer» C. | |
| 1028. |
Two voltages 50 V each have a phase difference of 45°. The rms value of resultant sum of the two voltages is |
| A. | 70.7 V |
| B. | 80.4 V |
| C. | 92.4 V |
| D. | 100 V |
| Answer» D. 100 V | |
| 1029. |
The expression for the resonant frequency ω0 in the circuit shown |
| A. | 1/LC |
| B. | |
| Answer» C. | |
| 1030. |
An active network has |
| A. | an e.m.f source |
| B. | a current source |
| C. | neither of the above |
| D. | either (a) or (b) |
| Answer» E. | |
| 1031. |
In figure the effective resistance faced by voltage source is |
| A. | 1 Ω |
| B. | 2 Ω |
| C. | 3 Ω |
| D. | 3.3 Ω |
| Answer» C. 3 Œ© | |
| 1032. |
Paley Wiener criterion states that a necessary and sufficient condition for an amplitude function |H(jω)| to be causal is that |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1033. |
A system is at rest for t < 0. It is given by If steady state is reached at t = 0, then the value of angle A is given by |
| A. | 0 |
| B. | 45 ° |
| C. | - 45° |
| D. | ‚àû |
| Answer» C. - 45¬∞ | |
| 1034. |
Reciprocity theorem is applicable to |
| A. | circuits with one source |
| B. | circuits with only one independent source |
| C. | circuits with any number of sources |
| D. | circuits with any number of independent sources |
| Answer» C. circuits with any number of sources | |
| 1035. |
In the circuit of figure the current through 3 Ω resistance at t = 0+ is |
| A. | 0.16666666666667 |
| B. | 2.5 A |
| C. | 3.1 A |
| D. | 0 |
| Answer» E. | |
| 1036. |
In figure, the switch has been in closed position for a long time. At t = 0, the switch is opened. At t = 0+, the current R1 is |
| A. | 0.33333333333333 |
| B. | 0.16666666666667 |
| C. | 0.25 |
| D. | 0.083333333333333 |
| Answer» C. 0.25 | |
| 1037. |
In the following non-planar graph no.of independent loop equations are |
| A. | 8 |
| B. | 12 |
| C. | 7 |
| D. | 5 |
| Answer» E. | |
| 1038. |
Assertion (A): The response of a network to unit impulse can be obtained directly from the network function.Reason (R): The response of a network for any input can be obtained from impulse response. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true and R is not the correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are true and R is not the correct explanation of A | |
| 1039. |
A series RL circuit is switched on to an impulse. A δ(t) at t = 0. Then |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1040. |
An RL admittance function can also be realized as |
| A. | RC admittance function |
| B. | RC impedance function |
| C. | LC admittance function |
| D. | LC impedance function |
| Answer» C. LC admittance function | |
| 1041. |
In a specimen of cast iron, a field strength of 400 AT/m cause a flux density of 0.6 T. In a specimen of silicon steel, the same value of H would cause B to be |
| A. | 0.6 T |
| B. | more than 0.6 T |
| C. | less than 0.6 T |
| D. | 0.6 T or less than 0.6 T |
| Answer» E. | |
| 1042. |
Two port circuits are connected in parallel. To determine the response, it is more convenient to use |
| A. | O.C. impedance parameters |
| B. | S.C. admittance parameters |
| C. | ABCD parameters |
| D. | h parameters |
| Answer» C. ABCD parameters | |
| 1043. |
RMS value of a square wave is the same as peak value. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1044. |
The parallel RLC circuit shown in figure is in resonance. If |
| A. | IR < 1 mA |
| B. | | IR + IL | > 1 mA |
| C. | | IR + IL | < 1 mA |
| D. | | IL + IC | > 1 mA |
| Answer» C. | IR + IL | < 1 mA | |
| 1045. |
A series resonant circuit has inductance L. If L is increased, the resonant frequency |
| A. | increases |
| B. | decreases |
| C. | remains constant |
| D. | may increases or decreases |
| Answer» C. remains constant | |
| 1046. |
In the circuit shown in the given figure, RL will absorb maximum power when its value is |
| A. | 2.75 Ω |
| B. | 7.5 Ω |
| C. | 25 Ω |
| D. | 27 Ω |
| Answer» D. 27 Œ© | |
| 1047. |
In figure, the switch is closed at t = 0. At t = 0+ The value of current supplied by battery is |
| A. | 0.041666666666667 |
| B. | 0.083333333333333 |
| C. | zero |
| D. | infinity |
| Answer» B. 0.083333333333333 | |
| 1048. |
The following circuit resonates at |
| A. | 0.5 Hz |
| B. | 5 Hz |
| C. | 1 rad/sec |
| D. | 0.5 rad/sec |
| Answer» E. | |
| 1049. |
If V = 100 ∠ 16°, the (V) is |
| A. | 10 ∠ 32° |
| B. | 10 ∠ 8° |
| C. | 10 ∠ 16° |
| D. | 10 ∠ 4° |
| Answer» C. 10 ‚à† 16¬∞ | |
| 1050. |
In a power system, reactive power is necessary for |
| A. | power transmission |
| B. | stabilising the voltage level |
| C. | counteracting the effect of reactance in the transmission system |
| D. | none of the above |
| Answer» D. none of the above | |