Description : Is coupling loss from fiber separation and lateral misalignment more critical in expanded-beam or butt-jointed connectors?
Last Answer : Butt-jointed connectors.
Description : Is coupling loss from angular misalignment more critical in expanded beam or butt-jointed connectors?
Last Answer : Expanded beam connectors.
Description : A flange coupling is used to connect two shafts A. Which are perfectly aligned B. Which are not in exact alignment C. Have lateral misalignment D. Whose axes intersect at a small angle
Last Answer : A. Which are perfectly aligned
Description : Oldham coupling is used to connect two shafts A. Which are perfectly aligned B. Which are not in exact alignment C. Which have lateral misalignment D. Whose axes intersect at a small angle
Last Answer : C. Which have lateral misalignment
Description : A universal coupling is used to connect two shafts A. Which are not in exact alignment B. Which are perfectly aligned C. Whose axes intersect at a small angle D. Have lateral misalignment
Last Answer : C. Whose axes intersect at a small angle
Description : Does coupling loss from refractive index profile difference result when the receiving fiber has a larger profile parameter
Last Answer : Fiber alignment.
Description : What connection properties result in fiber optic connector coupling loss?
Last Answer : Poor fiber alignment and end preparation, fiber mismatches, and Fresnel reflection.
Description : Fiber-to-fiber coupling loss is affected by intrinsic and extrinsic coupling losses. Can intrinsic coupling losses be limited by limiting fiber mismatches?
Last Answer : Yes.
Description : Will fiber coupling loss generally increase or decrease if the mode field diameter of a single mode fiber is decreased?
Last Answer : Increase.
Description : Which of the following cannot tolerate misalignment? (a) Angular contact bearing (b) Cylinder roller bearing (c) Thrust ball bearings (d) All of the listed
Last Answer : (d) All of the listed
Description : Which of the following cannot tolerate misalignment? a) Angular contact bearing b) Cylinder roller bearing c) Thrust ball bearings d) All of the listed
Last Answer : d) All of the listed
Description : Given below are four statements pertaining to separation of DNA fragments using gel electrophoresis. Identify the incorrect statements. (i) DNA is negatively charged molecule and so it is loaded on gel towards the anode terminal. (ii) DNA ... (iii) (c) (ii), (iii) and (iv) (d) (i), (ii) and (iv)
Last Answer : (d) (i), (ii) and (iv)
Description : What is the basic fiber cleaving technique for preparing optical fibers for coupling?
Last Answer : Score-and-break.
Description : In fiber-to-fiber connections, Fresnel reflection is one source of coupling losses. Light is reflected back into the source fiber and is lost. What causes Fresnel reflection?
Last Answer : A step change in refractive index that occurs at fiber joints, caused by fiber separation.
Description : How are source-to-fiber coupling and microbending and macrobending losses affected by changes in core diameter and D?
Last Answer : Coupling efficiency increases with both core diameter and D, while bending losses increase directly with core diameter and inversely with D.
Description : As the core and cladding modes travel along the fiber, mode coupling occurs. What is mode coupling?
Last Answer : Mode coupling is the exchange of power between two modes.
Description : optical launch conditions exists if the launch spot size and angular distribution are larger than that of the fiber core?
Last Answer : Overfilled.
Description : Microbend loss is caused by microscopic bends of the fiber axis. List three sources of microbend loss.
Last Answer : Uneven coating applications, improper cabling procedures, and external force.
Description : When the axes of two connected fibers are no longer in parallel, the two connected fibers are in what kind of misalignment?
Last Answer : Angular misalignment.
Description : The dominant loss mechanisms in silica fiber are ∙ a. Absorption and radiation losses ∙ b. Absorption and Rayleigh scattering ∙ c. Coupling and radiation losses ∙ d. Radiation and modal dispersion
Last Answer : b. Absorption and Rayleigh scattering
Description : What are the main causes of coupling loss?
Last Answer : Poor fiber end preparation and poor fiber alignment.
Description : A switchboard ammeter indicates a reading slightly above 'zero' when the leads are disconnected, this is caused by _____________. A. mechanical misalignment of the meter pointer B. a poor ground for the meter case C. static electricity in the air D. capacitors inside the meter storing charges
Last Answer : Answer: A
Description : Reduction of Fresnel reflection is possible by reducing the step change in the refractive index at the fiber interface. What material reduces the step change in refractive index at a fiber interface?
Last Answer : Index matching gel.
Description : Why can multimode graded-index fiber 1300-nm systems using LEDs operate over longer distances and at higher bandwidths than 850-nm systems?
Last Answer : Longer distances and higher bandwidths are possible because fiber material losses and dispersion are significantly reduced at the 1300-nm region.
Description : What are the most distinguishing characteristics of a multimode graded-index fiber?
Last Answer : Source-to-fiber coupling efficiency and insensitivity to microbending and macrobending losses.
Description : What multimode graded-index fiber offers the best overall performance for most applications?
Last Answer : 62.5/125 mm multimode graded-index fiber.
Description : Light travels faster in a material with a lower refractive index. Therefore, light rays that travel a longer distance in a lower refractive index travel at a greater average velocity. What effect does this have on multimode graded-index fiber modal dispersion and bandwidth?
Last Answer : Decreases the time difference between light rays, which reduces modal dispersion and increases fiber bandwidth.
Description : In multimode step-index fibers, the majority of light propagates in the fiber core for what reason?
Last Answer : Most modes in multimode step-index fibers propagate far from cutoff.
Description : Multimode optical fibers can have a step-index or graded index refractive index profile. Which fiber, multimode step-index or multimode graded-index fiber, usually performs better?
Last Answer : Multimode graded-index fiber
Description : The refractive index of a fiber core is uniform and undergoes an abrupt change at the corecladding boundary. Is this fiber a step-index or graded-index fiber?
Last Answer : graded-index fiber?
Description : The index of refraction measures the speed of light in an optical fiber. Will light travel faster in an optically dense material or in one that is less dense?
Last Answer : Light will travel faster in an optical material that is less dense.
Description : Gel electrophoresis is used for (a) construction of recombinant DNA by joining with cloning vectors (b) isolation of DNA molecules (c) cutting of DNA into fragments (d) separation of DNA fragments according to their size.
Last Answer : (d) separation of DNA fragments according to their size.
Description : The rotating shaft or rotor vibrates with excessive lateral vibration at angular speed at which occurs is called as A) rotating speed B) critical speed C) vibrating speed D) None of the above
Last Answer : B) critical speed
Description : What two properties of the launch condition may affect multimode fiber attenuation measurements?
Last Answer : . Launch spot size and angular distribution.
Description : Scattering losses are caused by the interaction of light with density fluctuations within a fiber. What are the two scattering mechanisms called when the size of the density fluctuations is (a) greater than and (b) less than one-tenth of the operating wavelength?
Last Answer : . (a) Mie scattering; (b) Rayleigh scattering.
Description : Angular separation between two colours of the spectrum depends upon which thing? -General Knowledge
Last Answer : The answer is 'Angle of deviation'
Last Answer : answer:
Description : Angular separation between two colours of the spectrum depends upon which thing?
Last Answer : Angle of deviation
Description : The angular separation between the vectors A = 4i + 3j + 5k and B = i – 2j + 2k is (in degrees) a) 65.8 b) 66.8 c) 67.8 d) 68.8
Last Answer : c) 67.8
Description : 1. What is Study of growth and development of embryo? 2. What is the minimum permissible age for employment in any factory or mine? 3. Angular separation between two colours of the spectrum depends ... exporting iron ore to Japan? 20. Which site, where Ashokan pillars exist, has the bull capital?
Last Answer : Answer : 1. Embryology 2. 14 years 3. Angle of deviation 4. Aravallis 5. Neolithic Age 6. Vienna 7. Arundhati Roy 8. Sphygmology 9. The Great Himalayan Range 10. Second and seventh 11. ... First 14. Rajasthan 15. Mahavira 16. Thomas Paine 17. Soyabean 18. President 19. Paradeep 20. Rampurva
Description : Which type of optical splitter (Y-coupler or T-coupler) splits only a small amount of power from the input fiber to one of the output fibers?
Last Answer : T-coupler
Description : The amount of optical power coupled into an optical fiber depends on what four factors?
Last Answer : (1) The angles over which the light is emitted. (2) The size of the source's light-emitting area relative to the fiber core size. (3) The alignment of the source and fiber. (4) The coupling characteristics of the fiber (such as the NA and the refractive index profile)
Description : What fiber property directly affects splice loss in fusion splicing?
Last Answer : The angles and quality of the two fiber-end faces.
Description : Give two reasons why optical fiber manufacturers depart from the traditional circular core and cladding, low-loss glass fiber design?
Last Answer : To increase performance and reduce cost
Description : While coupled power and bending loss favor a high D, which Dvalue, smaller or larger, improves fiber bandwidth?
Last Answer : Smaller.
Description : Which type of optical fiber (multimode or single mode) tends to have lower loss and produces less signal distortion?
Last Answer : Single mode fiber.
Description : In 1969, what did several scientists conclude about optical fiber loss?
Last Answer : mpurities in the fiber material caused the signal loss in optical fibers. The basic fiber material did not prevent the light signal from reaching the end of the fiber.
Description : Which is not a possible cause of optical fiber loss? ∙ a. Impurities ∙ b. Glass attenuation ∙ c. Stepped index operation ∙ d. Microbending
Last Answer : ∙ c. Stepped index operation
Description : Loose or inefficient coupling of energy into or out of a waveguide can be accomplished by the use of what method?
Last Answer : Slots and apertures.