Description : The cutoff wavelength of matched-clad and depressed-clad single mode fibers varies according to the fiber's radius of curvature and length. The cutoff wavelength of which single mode fiber type is more sensitive to length
Last Answer : Depressed-clad.
Description : When electrical cables penetrate watertight bulkheads, _______________. A. they should be grounded on either side of the bulkhead B. they must be bent to a radius of six diameters C. a watertight stuffing tube capable of accepting packing should be employed D. they should be secured by a clamp
Last Answer : Answer: C
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 : Which type of fiber optic connector (butt-jointed or expanded beam) brings the prepared ends of two optical fibers into close contact?
Last Answer : Butt-jointed connectors.
Description : What is the basic fiber cleaving technique for preparing optical fibers for coupling?
Last Answer : Score-and-break.
Description : Which semiconductor sources (LD or LED) emit more focused light and are capable of launching sufficient optical power into both single mode and multimode fibers?
Last Answer : LDs.
Description : List the three techniques used by manufacturers to buffer optical fibers.
Last Answer : Tight-buffered, loose-tube, and gel-filled loose-tube.
Description : List three benefits that properly cabled optical fibers provide.
Last Answer : a. Protect optical fibers from damage or breakage during installation and over the fiber's lifetime. b. Provide stable fiber transmission characteristics compared with uncabled fibers. c. Maintain the physical integrity of the optical fiber.
Description : List the types of materials used in fabricating low-loss, long wavelength optical fibers.
Last Answer : Heavy-metal fluorides, chalcogenide glasses, and crystalline materials.
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 : A mode filter is a device that attenuates specific modes propagating in the core of an optical fiber. What mode propagating along single mode fibers do mode filters eliminate?
Last Answer : Second-order mode.
Description : Will an optical fiber's attenuation coefficient vary with changes in wavelength?
Last Answer : Yes.
Description : What are the two basic types of optical fibers?
Last Answer : Multimode and single mode fibers.
Description : How can loss be reduced during construction (or fabrication) of optical fibers?
Last Answer : By removing the impurities from optical fiber.
Description : When is an optical power meter measurement recommended for conducting field measurements on installed optical fiber cables or cable plants?
Last Answer : When an installed optical fiber cable or cable plant is less than 50 meters in length.
Description : A light ray incident on the optical fiber core is propagated along the fiber. Is the angle of incidence of the light ray entering the fiber larger or smaller than the acceptance angle
Last Answer : Smaller.
Description : In single mode operation, the value of the normalized frequency (V) should remain near the 2.405 level. If the value of V is less than 1, do single mode fibers carry a majority of the power in the core or cladding material?
Last Answer : Cladding material.
Description : Will the cutoff wavelength of uncabled fibers (lcf) generally have a value higher or lower than the cutoff wavelength of cabled fibers (λcc)?
Last Answer : Higher.
Description : They experimented with light transmission cables through bundle of fibers and lead to the development of flexible fiberscope. ∙ A. Townes, Schawlow and Kao ∙ B. Maiman, Kao and Bockham ∙ C. Maurer, Kapron and Keck ∙ D. Van Heel, Hopkins and Kapany
Last Answer : D. Van Heel, Hopkins and Kapany
Description : They experimented with light transmission cables through bundle of fibers and lead to the development of flexible fiberscope
Last Answer : Van Heel, Hopkins and Kapany
Description : Give two reasons why the value of the normalized frequency (V) is varied in single mode stepindex fibers?
Last Answer : To increase performance and reduce losses caused by bending and splicing.
Description : The value of the normalized frequency parameter (V) relates the core size with mode propagation. When single mode fibers propagate only the fundamental mode, what is the value of V?
Last Answer : V≤2.405.
Description : The fiber's normalized frequency (V) determines how many modes a fiber can support. As the value of V increases, will the number of modes supported by the fiber increase or decrease?
Last Answer : Increase.
Description : The maximum value of hoop compression in a dome is given by (A) wR / 4d (B) wR/2d (C) wR/d (D) 2wR/d Where, w = load per unit area of surface of dome R = radius of curvature d = thickness of dome
Last Answer : (B) wR/2d
Description : Jam nut is a locking device in which (A) A smaller nut is tightened against main nut creating friction at the contacting surface (B) A split pin is passed through diametrically opposite slots in nut and ... parts of nut separated by slot (D) An elastic piece is tightened in the nut by a setscrew
Last Answer : (A) A smaller nut is tightened against main nut creating friction at the contacting surface
Description : Castle nut is a locking device in which (A) A smaller nut is tightened against main nut creating friction at the contacting surface (B) A split pin is passed through diametrically opposite slots in nut and ... of nut separated by slot (D) An elastic piece is tightened in the nut by a setscrew
Last Answer : (B) A split pin is passed through diametrically opposite slots in nut and a hole in bolt and the two ends of split pin are separated and bent back on nut
Description : Optical fibers are the fine strands of _____. A. Glass B. Iron C. Calcium D. Mercury
Last Answer : ANSWER: A
Description : Optical Fiber Optical fibers are the fine strands of _____. A. Glass B. Iron C. Calcium D. Mercury
Description : _______uses two optical fibers anda long-wavelaser source. A) 1000Base-SX B) 1000Base-LX C) 1000Base-T D) none of the above
Last Answer : 1000Base-LX
Description : ______ uses two optical fibers and a short-wave laser source, A) 1000Base-SX B) 1000Base-LX C) 1000Base-T D) none of the above
Description : Optical fibers for telecommunications are typically about _____ mils thick and consists of a glass core, a glass cladding of lower index of refraction, and a protective coating ∙ a. 5 ∙ b. 6 ∙ c. 7 ∙ d. 8
Last Answer : ∙ a. 5
Description : The ultrapure glass used to manufacture optical fibers is approximately ___pure ∙ a. 99.9 % ∙ b. 99.99 % ∙ c. 99.999 % ∙ d. 99.9999 %
Last Answer : d. 99.9999 %
Description : Unlike coax and twisted pair, optical fibers are immune to a. High-frequency transmission b. Signal attenuation c. Power loss d. Electromagnetic interference
Last Answer : Unlike coax and twisted pair, optical fibers are immune to Electromagnetic interference
Description : Light travels along optical fibers by
Last Answer : Light travels along optical fibers by Total internal reflection
Description : An object is placed beyond 2F, in front of a convex lens, image will be formed : (a) between F and 2F (b) at focus (c) at the centre of curvature (d) between focus and Optical centre
Last Answer : (a) between F and 2F
Description : Why are the ends of the deflection plates bent outward?
Last Answer : To permit wide-angle deflection of the bea
Last Answer : To permit wide-angle deflection of the beam.
Description : An infinitely long conductor is bent into a circle as shown in figure. It carries a current I ampere and the radius of loop is R metre. The magnetic i
Last Answer : An infinitely long conductor is bent into a circle as shown in figure. It carries a current I ampere and the radius ... (0)I)/(8piR)(pi + 1)` D. zero
Description : A current `-` carrying circular loop of radius `R` is placed in the `XY-` plane with centre at the origin. Half of the loop with `xgt0` is now bent so
Last Answer : A current `-` carrying circular loop of radius `R` is placed in the `XY-` plane with centre at the origin. ... B at (0,0,z), z gt gt R is unchanged
Description : In the following figure a wire bent in the form of a regular polygon of `n` sides is inscribed in a circle of radius `a`. Net magnetic field at centre
Last Answer : In the following figure a wire bent in the form of a regular polygon of `n` sides is inscribed in a circle of ... (ni)/(a)mu_(0)tan.(pi)/(n)` D.
Description : A thin wire is in the shape of a circle of radius 77 cm. It is bent into a square. What is the side of the square? (a) 168 cm (b) 242 cm (c) 121 cm (d) 336 cm
Last Answer : (c) 121 cm
Description : A wire can be bent to form a circle of radius 56 cm. if it is instead bent in the form of a square, then its area will be: a) 6400 sq.cm b) 2025 sq.cm c) 7744 sq.cm d) 6561 sq.cm e) none of these
Last Answer : Length of the wire = circumference of the circle 2 × (22/7) × 56 = 2 × 22 × 8 = 352 cm side of square = 352/4 = 88cm area of square = 88 × 88 = 7744 sq.cm Answer: c)
Description : These bends are caused by excessive pressure and tension and generally occur while fiber are bent during handling or installation. ∙ A. microbending ∙ B. macrobending ∙ C. constant-radius bending ∙ D. kinks
Last Answer : C. constant-radius bending
Description : The human lens: a. is innervated by the ophthalmic nerve b. has a uniform refractive index c. has a large radius of curvature anteriorly than posteriorly d. stops growing after birth
Last Answer : has a large radius of curvature anteriorly than posteriorly
Description : The following are true about the lens: a. the anterior capsule is 10 times thicker than the posterior capsule b. the anterior surface has a greater radius of curvature than the posterior surface c ... the cornea d. the lens is more effective in absorbing light with long than short wave-lengths
Last Answer : during accommodation the lens moves towards the cornea
Description : Which are more sensitive to alignment errors, single mode or multimode fibers?
Last Answer : Single mode.
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 : Do small core distortions formed by arc fusion's self alignment mechanism have more of an affect on light propagating through multimode or single mode fibers?
Last Answer : Single mode fibers.
Description : What are the two methods used by fiber manufacturers to fabricate multimode and single mode glass fibers?
Last Answer : Vapor phase oxidation and direct-melt process.