MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
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.
| 201. |
Which of the following noise does not occur in transistors? |
| A. | Partition noise |
| B. | Shot noise |
| C. | Flicker noise |
| D. | Resistance noise |
| Answer» B. Shot noise | |
| 202. |
FM amplifier in a superheterodyne receiver |
| A. | increases selectivity |
| B. | suppresses noise |
| C. | provides improved tracking |
| D. | improves the rejection of the image frequency |
| Answer» E. | |
| 203. |
In a radio receiver, the local oscillator is tuned to a frequency |
| A. | lower than the incoming frequency |
| B. | higher than the incoming frequency |
| C. | equal to incoming frequency |
| D. | any of the above |
| Answer» C. equal to incoming frequency | |
| 204. |
The geostationary communication satellite APPLE is parked in the equatorial orbit at |
| A. | 102 E longitude over Sumatra |
| B. | 90 E longitude over Bangladesh |
| C. | 74 E longitude over India |
| D. | 67 E longitude over Pakistan |
| Answer» B. 90 E longitude over Bangladesh | |
| 205. |
Satellite launch sites are invariably located on Eastern seaboards to ensure that |
| A. | launch takes place eastward |
| B. | expenditure of propulsion fuel is reduced during plane changing |
| C. | the satellite achieves circular orbit quickly |
| D. | spent rocket motor and other launcher debris falls into the sea |
| Answer» E. | |
| 206. |
To make antenna more directional, either its size must be increased or |
| A. | the number of its feed horns must be increased |
| B. | the frequency of its transmission must be increased |
| C. | its effective isotropic radiated power (EIRP) must be increased |
| D. | its footprint must be increased |
| Answer» C. its effective isotropic radiated power (EIRP) must be increased | |
| 207. |
India's first domestic geostationary satellite 1NSAT-IA was launched on 10th April 1982 from |
| A. | USSR |
| B. | USA |
| C. | UK |
| D. | UP |
| Answer» C. UK | |
| 208. |
The most effective anti jamming technique is |
| A. | frequency hopping |
| B. | spread-spectrum modulation |
| C. | key leverage |
| D. | once-only key |
| Answer» C. key leverage | |
| 209. |
For satellite communication, standard Earth stations have antenna diameters in the range of __________ metre. |
| A. | 27.5 to 30 |
| B. | 10 to 15 |
| C. | 30 to 50 |
| D. | 5 to 10 |
| Answer» B. 10 to 15 | |
| 210. |
The owner of a communication satellite is usually required to keep the spacecraft on station at its assigned place in the geosynchronous orbit with an accuracy of __________ degree. |
| A. | 0.1 |
| B. | 1.0 |
| C. | 2.0 |
| D. | 0.5 |
| Answer» B. 1.0 | |
| 211. |
Power received from Sun per m2 surface area of a geosynchronous satellite in nearly __________ watt. |
| A. | 100 |
| B. | 500 |
| C. | 2000 |
| D. | 1000 |
| Answer» E. | |
| 212. |
A certain sound has 10000 times more energy than another sound. The number of times it would sound stronger to a listener is |
| A. | 40 |
| B. | 10000 |
| C. | 100 |
| D. | 10 |
| Answer» B. 10000 | |
| 213. |
The quality of a space-link is measured in terms of the __________ ratio. |
| A. | C/N |
| B. | S/N |
| C. | G/T |
| D. | EIRP |
| Answer» B. S/N | |
| 214. |
The useful operational life of INSAT-IB (launched in 1983) is expected to end by |
| A. | 1992-93 |
| B. | 1991-92 |
| C. | 1989-90 |
| D. | 1993-94 |
| Answer» D. 1993-94 | |
| 215. |
Orbital disturbances of a geosynchronous satellite are caused by the |
| A. | moon |
| B. | sun |
| C. | earth |
| D. | all of the above |
| Answer» E. | |
| 216. |
If , the coefficient of term e-t in f(t) will be |
| A. | 1 |
| B. | 0 |
| C. | 0.5 |
| D. | 2/3 |
| Answer» E. | |
| 217. |
A signal g(t) = A then g(t) is a |
| A. | energy signal |
| B. | power signal |
| C. | neither energy nor power signal |
| D. | insufficient data |
| Answer» C. neither energy nor power signal | |
| 218. |
The Fourier series of an odd periodic function contains |
| A. | odd harmonics only |
| B. | even harmonics only |
| C. | cosine harmonics only |
| D. | sine harmonics only |
| Answer» E. | |
| 219. |
The number of days when Earth's shadow falls on a geosynchronous satellite is |
| A. | 88 |
| B. | 277 |
| C. | 5 |
| D. | 10 |
| Answer» B. 277 | |
| 220. |
A voltage wave having 5% fifth harmonic content is applied to a series RC circuit. The percentage fifth harmonic content in the current wave will be |
| A. | 5% |
| B. | more than 5% |
| C. | less than 5% |
| D. | equal or more than 5% |
| Answer» C. less than 5% | |
| 221. |
The final value theorem is |
| A. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-21-1.png"> |
| B. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-21-2.png"> |
| C. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-21-3.png"> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-21-4.png"> |
| Answer» B. <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-21-2.png"> | |
| 222. |
If |
| A. | - 12 |
| B. | 12 |
| C. | 20 |
| D. | - 20 |
| Answer» B. 12 | |
| 223. |
The analog signal m(t) is given below m(t) = 4 cos 100 pt + 8 sin 200 pt + cos 300 pt, the Nyquist sampling rate will be |
| A. | 1/100 |
| B. | 1/200 |
| C. | 1/300 |
| D. | 1/600 |
| Answer» D. 1/600 | |
| 224. |
Double integration of a unit step function would lead to |
| A. | an impulse |
| B. | a parabola |
| C. | a ramp |
| D. | a doublet |
| Answer» C. a ramp | |
| 225. |
The system with given pole-zero diagram is |
| A. | casual |
| B. | non-casual |
| C. | both sided |
| D. | not-possible |
| Answer» E. | |
| 226. |
A pole zero pattern of a certain filter is shown in figure. This filter must be |
| A. | LPF |
| B. | BFP |
| C. | HPF |
| D. | APF |
| Answer» E. | |
| 227. |
Laplace transform of a pulse function of magnitude E and duration from t = 0 to t = a is |
| A. | E / |
| B. | <i> s </i> |
| C. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-5-2.png"> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-5-3.png"> |
| E. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-5-4.png"> |
| Answer» D. <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/04-5-3.png"> | |
| 228. |
The z-transform of a particular signal is given whereThe system after implementation will be |
| A. | casual and stable |
| B. | non-casual and stable |
| C. | non-casual and unstable |
| D. | casual and unstable |
| Answer» B. non-casual and stable | |
| 229. |
If is the Laplace transform of f(t) then f(0+) is |
| A. | 0 |
| B. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/23-387-2.png"> |
| C. | 27 |
| D. | |
| Answer» D. | |
| 230. |
Z transform is a non-linear operation. |
| A. | True |
| B. | False |
| Answer» C. | |
| 231. |
An impulse function consist of |
| A. | pure dc |
| B. | pure a.c |
| C. | entire frequency range with constant phase |
| D. | infinite bandwidth with linear phase vaariations |
| Answer» D. infinite bandwidth with linear phase vaariations | |
| 232. |
Two function g1(t) and g2(t) with correlation of 6 has average power of 4 and 5 respectively. The power of g1(t) + g2(t) is |
| A. | 9 |
| B. | 21 |
| C. | 3 |
| D. | 15 |
| Answer» C. 3 | |
| 233. |
A box has 4 white and 3 red balls. Two balls are taken out in succession. What is the probability that both are white? |
| A. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/16-227-1.png"> |
| B. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/16-227-2.png"> |
| C. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/16-227-3.png"> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/16-227-4.png"> |
| Answer» D. <img src="/_files/images/electronics-and-communication-engineering/signals-and-systems/16-227-4.png"> | |
| 234. |
(t) is a |
| A. | energy signal |
| B. | power signal |
| C. | neither energy nor power |
| D. | none |
| Answer» C. neither energy nor power | |
| 235. |
If I (s) , initial value of i(t) is |
| A. | 5A |
| B. | 12.5 A |
| C. | 0.05 A |
| D. | 1250 A |
| Answer» B. 12.5 A | |
| 236. |
The analog signal given below is sampled by 600 samples per second for m(t) = 3 sin 500 pt + 2 sin 700 pt then folding frequency is |
| A. | 500 Hz |
| B. | 700 Hz |
| C. | 300 Hz |
| D. | 1400 Hz |
| Answer» D. 1400 Hz | |
| 237. |
If I (s) , the final value of i(t) is |
| A. | 5A |
| B. | 12.5 A |
| C. | 0.05 A |
| D. | 1250 A |
| Answer» C. 0.05 A | |
| 238. |
As compared to 17.34 antenna, the total increase in the signal relayed by 4.5 antenna of INTELSAT-IV is |
| A. | 14.85 |
| B. | 220 |
| C. | 78 |
| D. | 3.85 |
| Answer» C. 78 | |
| 239. |
Radio broadcasting is a familiar example of |
| A. | space multiplexing |
| B. | time multiplexing |
| C. | frequency multiplexing |
| D. | none of the above |
| Answer» D. none of the above | |
| 240. |
The selectivity of most receivers is determined largely by |
| A. | sensitivity |
| B. | characteristics of IF section |
| C. | antenna direction |
| D. | all of the above |
| Answer» C. antenna direction | |
| 241. |
In a broadcast superheterodynes receiver having no RF amplifier, the loaded Q of the antenna coupling circuit is 100. If the intermediate frequency is 455 kHz. The rejection ratio at 25 MHz will be |
| A. | 1.116 |
| B. | 1.386 |
| C. | 2.116 |
| D. | 2.386 |
| Answer» B. 1.386 | |
| 242. |
Which one of the following statements regarding DSI is wrong? |
| A. | It is a digital form of TASI |
| B. | Though it is more efficient than TASI, it is much slower |
| C. | A speaker has to wait (it at all) for only a few milliseconds for reallocation of channel |
| D. | It has increased the capacity of satellite channels by a factor of 2.2 or more with out degrading speech quality |
| Answer» C. A speaker has to wait (it at all) for only a few milliseconds for reallocation of channel | |
| 243. |
Which one of the following statements regarding compandor is FALSE? |
| A. | It compresses the higher-amplitude parts of a signal before modulation and expands them back to normal again after demodulation. |
| B. | It gives preferential treatment to the weaker parts of the signal |
| C. | For weaker signals it gives a poor ratio of signal strength to quantizing error |
| D. | Weaker signals, traverse more quantum steps than they would do otherwise and so quantizing error is reduced. |
| Answer» D. Weaker signals, traverse more quantum steps than they would do otherwise and so quantizing error is reduced. | |
| 244. |
In a superheterodyne receiver, the IF is 455 kHz. If it is tuned to 1200 kHz, the image frequency will be |
| A. | 1655 kHz |
| B. | 2110 kHz |
| C. | 745 kHz |
| D. | 910 kHz |
| Answer» C. 745 kHz | |
| 245. |
Standard AM radio broadcasts are confined to |
| A. | MF |
| B. | HF |
| C. | VHF |
| D. | UHF |
| Answer» B. HF | |
| 246. |
The noise produced by a resistor is proportional to |
| A. | absolute temperature |
| B. | (absolute temperature) |
| C. | <sup>2</sup> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/radio-receivers/06-52-3.png"> |
| E. | <img src="/_files/images/electronics-and-communication-engineering/radio-receivers/06-52-4.png"> |
| Answer» B. (absolute temperature) | |
| 247. |
The Sun blots out the transmission of a geosynchronous satellite twice a year when satellite passes directly in front of it. This outage lasts for about |
| A. | 10 minutes on 5 consecutive days |
| B. | 5 minutes on 10 consecutive days |
| C. | 30 minutes for 5 consecutive days |
| D. | one hour for 5 consecutive days |
| Answer» B. 5 minutes on 10 consecutive days | |
| 248. |
In satellite communication, frequency modulation is used because satellite channel has |
| A. | small bandwidth and negligible noise |
| B. | large bandwidth and severe noise |
| C. | maximum bandwidth and minimum noise |
| D. | high modulation index |
| Answer» C. maximum bandwidth and minimum noise | |
| 249. |
A transmitter serial current contains |
| A. | carrier frequencies |
| B. | audio frequencies |
| C. | radio frequencies |
| D. | none of the above |
| Answer» D. none of the above | |
| 250. |
Which of the following factor does NOT contribute to the drift of a geostationary satellite from its stationary position in space? |
| A. | Pressure of solar radiations |
| B. | Gravitational changes due to Sun and Moon |
| C. | Oblateness of the Earth |
| D. | Weight of the satellite |
| Answer» E. | |