MCQOPTIONS
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MCQOPTIONS
This section includes 259 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 201. |
In waveguide dispersion, refractive index is independent of |
| A. | bit rate |
| B. | index difference |
| C. | velocity of medium |
| D. | wavelength |
| Answer» E. | |
| 202. |
The optical source used in a fiber is an injection laser with a relative spectral width σλ/λ of 0.0011 at a wavelength of 0.70μm. Estimate the RMS spectral width. |
| A. | 1.2 nm |
| B. | 1.3 nm |
| C. | 0.77 nm |
| D. | 0.98 nm |
| Answer» D. 0.98 nm | |
| 203. |
Chromatic dispersion is also called as intermodal dispersion. |
| A. | true |
| B. | false |
| Answer» C. | |
| 204. |
A multimode graded index fiber exhibits a total pulse broadening of 0.15μsover a distance of 16 km. Estimate the maximum possible bandwidth, assuming no intersymbol interference. |
| A. | 4.6 mhz |
| B. | 3.9 mhz |
| C. | 3.3 mhz |
| D. | 4.2 mhz |
| Answer» D. 4.2 mhz | |
| 205. |
The maximum bit rate that may be obtained on an optical fiber link is 1/3Γ. |
| A. | true |
| B. | false |
| Answer» C. | |
| 206. |
For no overlapping of light pulses down on an optical fiber link, the digital bit rate BT must be |
| A. | less than the reciprocal of broadened pulse duration |
| B. | more than the reciprocal of broadened pulse duration |
| C. | same as that of than the reciprocal of broadened pulse duration |
| D. | negligible |
| Answer» B. more than the reciprocal of broadened pulse duration | |
| 207. |
Frequency domain measurement is the preferred method for acquiring the bandwidth of multimode optical fibers. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 208. |
Intra-modal dispersion tends to be dominant in multimode fibers. |
| A. | true |
| B. | false |
| Answer» C. | |
| 209. |
What does ISI stand for in optical fiber communication? |
| A. | invisible size interference |
| B. | infrared size interference |
| C. | inter-symbol interference |
| D. | inter-shape interference |
| Answer» D. inter-shape interference | |
| 210. |
In pulse dispersion measurements, the 3dB pulse broadening for the fiber is 10.5 ns/km and the length of the fiber is 1.2 km. Calculate the optical bandwidth for the fiber. |
| A. | 32 mhz km |
| B. | 45 mhz km |
| C. | 41.9 mhz km |
| D. | 10 mhz km |
| Answer» D. 10 mhz km | |
| 211. |
The time domain dispersion measurement setup involves                            as the photo detector. |
| A. | avalanche photodiode |
| B. | oscilloscope |
| C. | circulator |
| D. | gyrator |
| Answer» B. oscilloscope | |
| 212. |
How many domains support the measurements of fiber dispersion? |
| A. | one |
| B. | three |
| C. | four |
| D. | two |
| Answer» E. | |
| 213. |
Devices such as                        are used to simulate the steady-state mode distribution. |
| A. | gyrators |
| B. | circulators |
| C. | mode scramblers |
| D. | attenuators |
| Answer» D. attenuators | |
| 214. |
In the single mode fibers, the dominant dispersion mechanism is |
| A. | intermodal dispersion |
| B. | frequency distribution |
| C. | material dispersion |
| D. | intra-modal dispersion |
| Answer» E. | |
| 215. |
                       measurements give an indication of the distortion to the optical signals as they propagate down optical fibers. |
| A. | attenuation |
| B. | dispersion |
| C. | encapsulation |
| D. | frequency |
| Answer» C. encapsulation | |
| 216. |
How many types of mechanisms are present which produce dispersion in optical fibers? |
| A. | three |
| B. | two |
| C. | one |
| D. | four |
| Answer» B. two | |
| 217. |
Sharp bends or micro bends causes significant losses in fiber. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 218. |
How the potential macro bending losses can be reduced in case of multimode fiber? |
| A. | by designing fibers with large relative refractive index differences |
| B. | by maintaining direction of propagation |
| C. | by reducing the bend |
| D. | by operating at larger wavelengths |
| Answer» B. by maintaining direction of propagation | |
| 219. |
In the given equation, state what αr suggests? |
| A. | radius of curvature |
| B. | refractive index difference |
| C. | radiation attenuation coefficients |
| D. | constant of proportionality |
| Answer» D. constant of proportionality | |
| 220. |
Optical fibers suffer radiation losses at bends or curves on their paths. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 221. |
A single mode fiber has refractive indices n1=1.50, n2 = 2.23, core diameter of 8μm, wavelength = 1.5μm cutoff wavelength = 1.214μm. Find the radius of curvature? |
| A. | 12 mm |
| B. | 20 mm |
| C. | 34 mm |
| D. | 36 mm |
| Answer» D. 36 mm | |
| 222. |
Which of the following is not a metallic impurity found in glass in extrinsic absorption? |
| A. | fe2+ |
| B. | fe3+ |
| C. | cu |
| D. | si |
| Answer» E. | |
| 223. |
15, n2 = 1.11 and an operating wavelength of 0.7μm. Find the radius of curvature? |
| A. | 8.60μm |
| B. | 9.30μm |
| C. | 9.1μm |
| D. | 10.2μm |
| Answer» C. 9.1μm | |
| 224. |
The effects of intrinsic absorption can be minimized by |
| A. | ionization |
| B. | radiation |
| C. | suitable choice of core and cladding components |
| D. | melting |
| Answer» D. melting | |
| 225. |
Which of the following statements best explain the concept of material absorption? |
| A. | a loss mechanism related to the material composition and fabrication of fiber |
| B. | a transmission loss for optical fibers |
| C. | results in attenuation of transmitted light |
| D. | causes of transfer of optical power |
| Answer» B. a transmission loss for optical fibers | |
| 226. |
How many mechanisms are there which causes absorption? |
| A. | one |
| B. | three |
| C. | two |
| D. | four |
| Answer» C. two | |
| 227. |
Absorption losses due to atomic defects mainly include |
| A. | radiation |
| B. | missing molecules, oxygen defects in glass |
| C. | impurities in fiber material |
| D. | interaction with other components of core |
| Answer» C. impurities in fiber material | |
| 228. |
Stripline and parallel plate waveguides support the TEM wave. State true/false. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 229. |
For a TEM wave to propagate in a medium, the medium has to be |
| A. | air |
| B. | insulator |
| C. | dispersive |
| D. | non dispersive |
| Answer» E. | |
| 230. |
Which type of transmission line accepts the TEM wave? |
| A. | copper cables |
| B. | coaxial cable |
| C. | rectangular waveguides |
| D. | circular waveguides |
| Answer» C. rectangular waveguides | |
| 231. |
The guided phase constant of a TEM wave in a waveguide with a phase constant of 2.8 units is |
| A. | 2.8 |
| B. | 1.4 |
| C. | infinity |
| Answer» B. 1.4 | |
| 232. |
The guided wavelength of a TEM wave in a waveguide having a wavelength of 5 units is |
| A. | 0 |
| B. | infinity |
| C. | 5 |
| D. | 1/5 |
| Answer» D. 1/5 | |
| 233. |
The cut off wavelength in the TEM wave will be |
| A. | 0 |
| B. | negative |
| C. | infinity |
| D. | 1/6 ghz |
| Answer» D. 1/6 ghz | |
| 234. |
Which component is non zero in a TEM wave? |
| A. | ex |
| B. | hz |
| C. | ez |
| D. | attenuation constant |
| Answer» B. hz | |
| 235. |
The cut off frequency of the TEM wave is |
| A. | 0 |
| B. | 1 ghz |
| C. | 6 ghz |
| D. | infinity |
| Answer» B. 1 ghz | |
| 236. |
In a transverse electric magnetic wave, which of the following will be true? |
| A. | e is transverse to h |
| B. | e is transverse to wave direction |
| C. | h is transverse to wave direction |
| D. | e and h are transverse to wave direction |
| Answer» E. | |
| 237. |
TEM wave can propagate in rectangular waveguides. State true/false. |
| A. | true |
| B. | false |
| Answer» C. | |
| 238. |
The linear variation of refractive index with the electric field is known as the |
| A. | linear implantation |
| B. | ionization |
| C. | koppel effect |
| D. | pockels effect |
| Answer» E. | |
| 239. |
A passive Y-junction beam splitter is also used as a switch. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 240. |
Propagation losses in slab and strip waveguides are smaller than the single mode fibre losses. |
| A. | true |
| B. | false |
| Answer» C. | |
| 241. |
Strip pattern in waveguide structures is obtained through |
| A. | lithography |
| B. | cryptography |
| C. | depletion of holes |
| D. | implantation |
| Answer» B. cryptography | |
| 242. |
Which of the following materials have refractive index near two? |
| A. | ga as |
| B. | zinc |
| C. | inp |
| D. | alsb |
| Answer» C. inp | |
| 243. |
Which of the following devices are less widely used in the field of optical fibre communications? |
| A. | acousto-optic devices |
| B. | regenerators |
| C. | reflectors |
| D. | optical translators |
| Answer» B. regenerators | |
| 244. |
The planar waveguides may be fabricated from glasses and other isotropic materials such as                        and |
| A. | octane and polymers |
| B. | carbon monoxide and diode |
| C. | fluorides and carbonates |
| D. | sulphur dioxide and polymers |
| Answer» E. | |
| 245. |
When the dimensions of the guide are reduced, the number of                        also decreases. |
| A. | propagating nodes |
| B. | electrons |
| C. | holes |
| D. | volume of photons |
| Answer» B. electrons | |
| 246. |
Fiber mostly suited in single-wavelength transmission in O-band is? |
| A. | low-water-peak non dispersion-shifted fibers |
| B. | standard single mode fibers |
| C. | low minimized fibers |
| D. | non-zero-dispersion-shifted fibers |
| Answer» C. low minimized fibers | |
| 247. |
                       waveguides are plagued by high losses. |
| A. | circular |
| B. | planar |
| C. | depleted |
| D. | metal-clad |
| Answer» E. | |
| 248. |
A fiber which is referred as non- dispersive shifted fiber is? |
| A. | coaxial cables |
| B. | standard single mode fibers |
| C. | o-band |
| D. | c-band and l-band |
| Answer» D. c-band and l-band | |
| 249. |
Single mode fibers allow single mode propagation; the cladding diameter must be at least |
| A. | twice the core diameter |
| B. | thrice the core diameter |
| C. | five times the core diameter |
| D. | ten times the core diameter |
| Answer» E. | |
| 250. |
Multimode graded index fibers with |
| A. | single mode fibers |
| B. | multimode step fibers |
| C. | coaxial cables |
| D. | multimode graded index fibers |
| Answer» B. multimode step fibers | |