MCQOPTIONS
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MCQOPTIONS
This section includes 905 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.
| 201. |
The logic function f(A, B, C) = m(0, 2, 4, 5, 6) can be represented by : |
| A. | 1 only |
| B. | 1, 2 only |
| C. | 1, 3 only |
| D. | 1, 2 and 3 |
| Answer» C. 1, 3 only | |
| 202. |
In the Taylor series expansion of exp(x) + sin(x) about the point x = p, the coefficient of (x - p)2 is |
| A. | exp (p) |
| B. | 0.5 exp (p) |
| C. | exp (p) + 1 |
| D. | exp (p) - 1 |
| Answer» C. exp (p) + 1 | |
| 203. |
Which one of the following compounds is widely used for making ferrites? |
| A. | FeO |
| B. | CuO |
| C. | MgO |
| D. | Fe2O3 |
| Answer» E. | |
| 204. |
A system has 12 poles or 2 zeros. Its high frequency asymptote in its magnitude plot has slope of |
| A. | -200 dB/decade |
| B. | -240 dB/decade |
| C. | -280 dB/decade |
| D. | -320 dB/decade |
| Answer» B. -240 dB/decade | |
| 205. |
The steady state error of a stable type 0 unity feedback system for a unit step function is : |
| A. | 0 |
| B. | |
| Answer» C. | |
| 206. |
Which of the following devices has the 'negative resistance' characteristic? |
| A. | Reflex klystron |
| B. | Gunn diode |
| C. | P-N-P transistor |
| D. | Magnetron |
| Answer» C. P-N-P transistor | |
| 207. |
The two numbers represent in signed 2's complement form are P = 11101101 and Q = 111001110. If Q subtracted from P, the value obtained in signed 2's complement form is |
| A. | 100000111 |
| B. | 111 |
| C. | 11111001 |
| D. | 111111001 |
| Answer» D. 111111001 | |
| 208. |
Four signalsm1 = cos (ω0t), m2(t) = cos (ω0t), m3(t) = 2 cos (ω0t) and m4(t) = cos (4 ω0t) are multiplexed by Time Division Multiplexing system. The commutator speed in rps is |
| A. | 2f0 |
| B. | 3f0 |
| C. | 4f0 |
| D. | 8f0 |
| Answer» E. | |
| 209. |
Which one of the following is applicable to any network-linear or non-linear, active or passive, time-varying or invariant - as long as Kirchhoff laws are not violated? |
| A. | Tellegen's theorem |
| B. | Reciprocity theorem |
| C. | Maximum power transfer theorem |
| D. | Superposition theorem |
| Answer» B. Reciprocity theorem | |
| 210. |
The energy of constant-amplitude complex valued exponential sequence is __________ (where A is the constant amplitude) |
| A. | 0 |
| B. | 1 |
| C. | ‚àû |
| D. | A2 |
| Answer» D. A2 | |
| 211. |
A signal occupies a band 5 kHz to 10 kHz. For proper error free reconstruction at what rate it should be sampled? |
| A. | 10 kHz |
| B. | 20 kHz |
| C. | 5 kHz |
| D. | (10 + 5) x 2 kHz |
| Answer» B. 20 kHz | |
| 212. |
Z = __________ |
| A. | C[A(B + C) + D] |
| B. | (AB + AC + D) |
| C. | (CA + AC + D) |
| D. | none of these |
| Answer» E. | |
| 213. |
Consider the following statements:For a master-slave J-K flip-flop, the toggle frequency is the maximum clock frequency at which the flip-flop will toggle reliably.the data input must precede the clock triggering edge transition time by time minimum time.the data input must remain fixed for a given time after, the clock triggering edge transition time for reliable operation.propagation delay time is equal to the rise time and fall time of the data. Which of the above statements is/are correct? |
| A. | 1, 2 and 3 |
| B. | 1 and 2 only |
| C. | 2 and 3 only |
| D. | 3 and 4 only |
| Answer» B. 1 and 2 only | |
| 214. |
Consider the following statements:For a square waveguide of cross-section 3m x 3m it has been found At 6 GHz dominant mode will propagateAt 4 GHz only dominant modes and evanescentAt 11 GHz all the modes and no higher order mode will propagateAt 7 GHz degenerate modes will propagate Which of the above statements are correct? |
| A. | 1 and 2 only |
| B. | 1, 2 and 4 |
| C. | 2 and 3 only |
| D. | 2, 3 and 4 |
| Answer» B. 1, 2 and 4 | |
| 215. |
Which of the following meters requires an external power source for its operation? |
| A. | P.M.M.C. meter |
| B. | Hot wire ammeter |
| C. | Electronic voltmeter |
| D. | Electrodynamometer |
| Answer» D. Electrodynamometer | |
| 216. |
Given (224)r = The value of the radix 'r' is : |
| A. | 5 |
| B. | 6 |
| C. | 7 |
| D. | 10 |
| Answer» B. 6 | |
| 217. |
On which bands, do the optical fibers operate? Ultra violet bandUltra high frequency bandVisible light bandInfrared band Select the correct answer from the codes given below: |
| A. | 1 only |
| B. | 1 and 2 only |
| C. | 1, 2 and only |
| D. | 1, 3 and 4 |
| Answer» E. | |
| 218. |
(29)13 √∑ (29)12 x (29)x = (23)16 Find x |
| A. | 11 |
| B. | 12 |
| C. | 13 |
| D. | 16 |
| Answer» C. 13 | |
| 219. |
The characteristic equation of a closed loop system is (s + 2) (s + 3) + K = 0. The centroid of the asymptotes in root locus is: |
| A. | 2.5 |
| B. | -2.5 |
| C. | 0.5 |
| D. | -0.5 |
| Answer» C. 0.5 | |
| 220. |
For the waveform shown below, the slew rate and full power bandwidth with respect to op-amp will be respectively |
| A. | 0.02 V/μsec, 1.59 KHz |
| B. | 0.04 V/μsec, 1.59 KHz |
| C. | 0.02 V/μsec, 3.58 KHz |
| D. | 0.02 V/μsec, 1.59 KHz |
| Answer» B. 0.04 V/Œºsec, 1.59 KHz | |
| 221. |
The Gain margin for the system with open loop transfer function : |
| A. | ‚àû |
| B. | 0 |
| C. | 1 |
| D. | -‚àû |
| Answer» B. 0 | |
| 222. |
An XOR gate with 8 variable is as follows: A ‚äï B ‚äï C ‚äï D ‚äï E ‚äï F ‚äï G ‚äï HThe number of minterms in the Boolean expression is |
| A. | 255 |
| B. | 127 |
| C. | 128 |
| D. | 256 |
| Answer» D. 256 | |
| 223. |
For the output F to be 1 in the logic circuit shown, the input combination should be |
| A. | A = 1, B = 1, C = 0 |
| B. | A = 1, B = 0, C = 0 |
| C. | A = 0, B = 1, C = 0 |
| D. | A = 0, B = 0, C = 1 |
| Answer» E. | |
| 224. |
Transmitted voltage level is: |
| A. | 11 |
| B. | 7.8 |
| C. | 7.348 V |
| D. | none of these |
| Answer» D. none of these | |
| 225. |
Noise with double-sided power spectral density of K overall frequencies is passed through a RC low pass filter with 3 dB cut-off frequency of fc. The noise power at the filter output is |
| A. | K |
| B. | Kfc |
| C. | Kpfc |
| D. | ‚àû |
| Answer» D. ‚àû | |
| 226. |
How many distinct binary trees can be constructed with three nodes? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 5 |
| Answer» E. | |
| 227. |
The step error coefficient of a system with unity feedback is : |
| A. | 43617 |
| B. | ‚àû |
| C. | 0 |
| D. | 1 |
| Answer» B. ‚àû | |
| 228. |
Effective Q of the equivalent electrical circuit of quartz crystal is of the order of |
| A. | 200 |
| B. | 2000 |
| C. | 20000 |
| D. | 200000 |
| Answer» D. 200000 | |
| 229. |
A coil has a designed for high Q performance at a rated voltage and a specified frequency. If the frequency of operation is doubled, and the coil is operated at the same rated voltage, then the Q factor and the active power P consumed by the coil will be affected as follows. |
| A. | P is doubled, Q is halved |
| B. | P is halved, Q is doubled |
| C. | P remains constant, Q is doubled |
| D. | P decreases 4 times, Q is doubled |
| Answer» E. | |
| 230. |
Locus of a point Z satisfying the equation arg is: |
| A. | Straight line with equation y = x - 3 |
| B. | Circle with equation x2 + y2 - 3x + 3y = 0 |
| C. | Hyperbola with equation x2 - y2 - 3x - 3y - 2yx = 0 |
| D. | None of these |
| Answer» C. Hyperbola with equation x2 - y2 - 3x - 3y - 2yx = 0 | |
| 231. |
The continuous time system with impulse response h(t) u(t) is stable, if __________ (n is even). |
| A. | a = 0 |
| B. | a > 0 |
| C. | a < 0 |
| D. | none of these |
| Answer» D. none of these | |
| 232. |
The system with given T.F. to be stable will be |
| A. | causal |
| B. | anticausal |
| C. | both sided |
| D. | non causal |
| Answer» E. | |
| 233. |
Personal computer cannot be used for which one of the following? |
| A. | Game playing |
| B. | Weather forecasting |
| C. | Office Automation |
| D. | Home computing |
| Answer» C. Office Automation | |
| 234. |
An open loop transfer function is given by has |
| A. | one zero at ‚àû |
| B. | two zeros at ‚àû |
| C. | three zeros at ‚àû |
| D. | four zeros at ‚àû |
| Answer» D. four zeros at ‚àû | |
| 235. |
In which one of the following types of analog to digital converts the conversion time is practically independent of the amplitude of the analog signal? |
| A. | The dual slope integrating type |
| B. | Successive approximation type |
| C. | Counter ramp type |
| D. | Tracking type |
| Answer» C. Counter ramp type | |
| 236. |
Conversion rate, for a successive approximation ADC which uses 2 MHz clock and 5 bit binary ladder containing 8 VV reference voltage is __________ . |
| A. | 64516.12 conversions/sec |
| B. | 400000 conversions/sec |
| C. | 400000 bps |
| D. | 2.5 bps |
| Answer» C. 400000 bps | |
| 237. |
Which one of the following logic families can be operated using a supply voltage from 3 V to 15 V? |
| A. | TTL |
| B. | ECL |
| C. | PMOS |
| D. | CMOS |
| Answer» E. | |
| 238. |
If over the path shown in the figure is |
| A. | 0 |
| B. | |
| C. | 1 |
| Answer» D. | |
| 239. |
If the characteristic equation of a closed loop system is s2 + 2s + 2, then the system is : |
| A. | over damped |
| B. | critically damped |
| C. | under damped |
| D. | undamped |
| Answer» D. undamped | |
| 240. |
When transistor is used as a switch __________ is defined as the interval which elapses between the transition of input waveform and the time when to transition to 90% of Ic(sat). |
| A. | storage time |
| B. | fall time |
| C. | turn-on time |
| D. | turn-off time |
| Answer» B. fall time | |
| 241. |
In the interconnection of ideal sources shown in the figure, it is known that the 60V source is absorbing powerWhich of the following can be the value of the current source? |
| A. | 0.41666666666667 |
| B. | 13 A |
| C. | 15 A |
| D. | 18 A |
| Answer» B. 13 A | |
| 242. |
For a npn BJT transistor fβ is 1.64 x 108 Hz. Cμ = 10-14 F; Cp = 4 x 10-13 F and DC current gain is 90. Find fT and gm (fβ = cut off frequency, Cμ = capacitance, Cp = parasitic capacitance, gm = transconductance, fT = gain BW product) |
| A. | fT = 1.47 x 1010 Hz ; gm = 38 milli mho |
| B. | fT = 1.64 x 108 Hz ; gm = 30 milli mho |
| C. | fT = 1.47 x 109 Hz ; gm = 38 mho |
| D. | fT = 1.33 x 1012 Hz; gm = 0.37 m-mho |
| Answer» B. fT = 1.64 x 108 Hz ; gm = 30 milli mho | |
| 243. |
The pre-emphasis in FM aids in providing extra noise immunity by |
| A. | emphasizing only the higher frequency components |
| B. | emphasizing the entire frequency band |
| C. | emphasizing only the lower frequency band |
| D. | cutting down the low frequency noise |
| Answer» D. cutting down the low frequency noise | |
| 244. |
The following statements are true with respect to "Cascode Amplifier". The reduction in h12 and Miller capacitance result in negligible reverse internal feedback. A's is large loads cannot be connected. As a narrow band amplifier, it provides small range of cμ is reduced. As a narrow band amplifier it provides small range of frequencies parameters the effect of cμ reduces. |
| A. | only 1 |
| B. | only 1 and 4 |
| C. | only 2 and 4 |
| D. | only 1 and 3 |
| Answer» C. only 2 and 4 | |
| 245. |
Identification of highest priority interrupt can be achieved in a minimum time by which of the following schemes? |
| A. | Hardwired polling |
| B. | Priority encode circuit |
| C. | Software polling |
| D. | Subdivision of interrupt register into a number of sub registers which are checked parallely |
| Answer» B. Priority encode circuit | |
| 246. |
Which of the following Boolean algebra rules is correct? |
| A. | A . A = 1 |
| B. | A + AB = A + B |
| C. | A + A B = A + B |
| D. | A(A + B) = B |
| Answer» D. A(A + B) = B | |
| 247. |
Manganin, an alloy of copper and manganese, is used in |
| A. | Soldering material |
| B. | Heating elements |
| C. | Ballast resistors |
| D. | Standard resistances |
| Answer» E. | |
| 248. |
An average response rectifier type electronic voltameter has a d.c. voltage of 10 V applied to it. What is the meter reading? |
| A. | 7.1 V |
| B. | 10 V |
| C. | 11.1 V |
| D. | 22.2 V |
| Answer» D. 22.2 V | |
| 249. |
If the connection of two-port is such that the transmission matrix of the overall network is the product of the transmission matrices of the individual networks, what type of connection is it? |
| A. | Series connection |
| B. | Cascade connection |
| C. | Parallel connection |
| D. | None of the above |
| Answer» C. Parallel connection | |
| 250. |
Find the power absorbed or delivered by each source: |
| A. | a = -32 b = - 12 c = -80 d = -60 |
| B. | a = -32 b = - 12 c = 80 d = 60 |
| C. | a = 32 b = 12 c = -80 d = 60 |
| D. | a = -32 b = 12 c = 80 d = -60 |
| Answer» E. | |