Description : Single frequency light is called ∙ A. pure ∙ B. intense ∙ C. coherent ∙ D. monochromatic
Last Answer : D. monochromatic
Description : Laser light is very bright because it is ∙ a. Pure ∙ b. White ∙ c. Coherent ∙ d. Monochromatic
Last Answer : c. Coherent
Description : ____ is a light that can be coherent ∙ a. Spontaneous emission ∙ b. Monochromatic and in-phase ∙ c. Narrow beam divergence ∙ d. Monochromatic
Last Answer : ∙ b. Monochromatic and in-phase
Description : How can modal dispersion reduced entirely? ∙ A. Use a graded index fiber ∙ B. Use a single-mode fiber ∙ C. Use a monochromatic light source ∙ D. Use a very sensitive light detector
Last Answer : Use a single-mode fiber
Description : Lasers are used to produce a) Intense beam of visible light b) monochromatic beam of visible light c) coherent beam of visible light d) All of them
Last Answer : d) All of them
Description : Chromatic dispersion can be eliminated by __________. ∙ A. using a monochromatic light source ∙ B. using a very small numerical aperture fiber ∙ C. using a graded-index fiber ∙ D. using a very sensitive photo detector
Last Answer : A. using a monochromatic light source
Description : . Is a non-coherent light source foe optical communications system. ∙ a. ILD ∙ b. LED ∙ c. APD ∙ d. PIN Diode
Last Answer : ∙ b. LED
Description : Laser light is ______ emission. ∙ a. Coherent ∙ b. Stimulated ∙ c. Spontaneous ∙ d. Coherent and stimulated
Last Answer : ∙ d. Coherent and stimulated
Description : The law that states “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted” is known as ____________. ∙ A. Einstein law of photon ∙ B. Marconi’s law ∙ C. Maxwell’s law ∙ D. Plank’s law
Last Answer : D. Plank’s law
Description : The laser frequency when the light has the wavelength 800 nm is ∙ a. 375 x 1012 Hz ∙ b. 475 x 1015 Hz ∙ c. 375 x 109 Hz ∙ d. 375 x 1018 Hz
Last Answer : d. 375 x 1018 Hz
Description : When a beam of light enters one medium from another, which quantity will not change? ∙ a. Direction ∙ b. Speed ∙ c. Frequency ∙ d. Wavelength
Last Answer : c. Frequency
Description : What generates a light beam of a specific visible frequency? ∙ a. Laser ∙ b. Maser ∙ c. Infrared ∙ d. Flashlight
Last Answer : ∙ a. Laser
Description : For a single mode optical cable with 0.25 dB/km loss, determine the optical power 100 km from a 0.1-mW light source. ∙ A. -45 dBm ∙ B. -15 dBm ∙ C. -35 dBm
Last Answer : ∙ C. -35 dBm
Description : More than one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode
Last Answer : A. Multimode
Description : Only one path for light rays to take down the fiber ∙ A. Multimode ∙ B. Step-index ∙ C. Single mode ∙ D. Graded index
Last Answer : C. Single mode
Description : It indicates what signal frequencies can be propagated through a given distance of fiber cable. ∙ A. Bandwidth Distance Product ∙ B. Pulse width dispersion ∙ C. Rise time ∙ D. Cutoff frequency
Last Answer : A. Bandwidth Distance Product
Description : Approximately what is the frequency limit of the optical fiber? ∙ A. 20 MHz ∙ B. 1 MHz ∙ C. 100 MHz ∙ D. 40 GHz
Last Answer : ∙ D. 40 GHz
Description : What is the frequency limit of a copper wire? ∙ A. approximately 0.5 MHz ∙ B. approximately 1.0 MHz ∙ C. approximately 40 GHz ∙ D. none of the above
Last Answer : B. approximately 1.0 MHz
Description : Which modulation methods are the most widely used in optical systems? ∙ a. Phase and frequency modulations ∙ b. Polarization modulation and phase modulation ∙ c. Intensity modulation and phase modulation ∙ d. Intensity modulation and polarization modulation
Last Answer : Intensity modulation and polarization modulation
Description : What is the frequency limit of an optical fiber? ∙ a. 20 GHz ∙ b. 30 GHz ∙ c. 40 GHz ∙ d. 50 GHz
Last Answer : ∙ c. 40 GHz
Description : The bandwidth of a fiber is limited by ∙ a. Mode ∙ b. Wavelength ∙ c. Dispersion ∙ d. Frequency
Last Answer : c. Dispersion
Description : What is the photon energy for an infrared wave with frequency of 1012 Hz? ∙ a. 10.6 x 1034 joules ∙ b. 6.63 x 10-34 joules ∙ c. 6.63 x 10-22 joules ∙ d. 10.6 x 1022 joules
Last Answer : ∙ c. 6.63 x 10-22 joules
Description : Which type of fiber-optic cable is the most widely used? ∙ A. single-mode step-index ∙ B. multimode step-index ∙ C. single-mode graded index ∙ D. multimode graded index
Last Answer : B. multimode step-index
Description : Single-mode step-index cable has a core diameter in the range of ∙ A. 100 to 1000 micrometer ∙ B. 50 to 100 micrometer ∙ C. 2 to 15 micrometer ∙ D. 5 to 20 micrometer
Last Answer : . 2 to 15 micrometer
Description : Which of the following is not a common type of fiber-optic cable? ∙ A. single-mode step-index ∙ B. multimode graded-index ∙ C. single-mode graded-index ∙ D. multimode step-index
Last Answer : . single-mode graded-index
Description : Which type of fiber optic cable is best for very high speed data? ∙ A. single-mode step-index ∙ B. multimode step-index ∙ C. single-mode graded-index ∙ D. multimode graded-index
Last Answer : A. single-mode step-index
Description : Which type of fiber-optic cable has the least modal dispersion? ∙ A. single-mode step-index ∙ B. multimode step-index ∙ C. single-mode graded-index ∙ D. multimode graded-index
Description : A type of index of an optical fiber that has no cladding and whose central core has a non-uniform refractive index. ∙ A. graded index ∙ B. multimode ∙ C. single mode ∙ D. step-index
Last Answer : ∙ A. graded index
Description : A type of index profile of an optical fiber that has a central core and outside cladding with a uniform refractive index ∙ A. multimode ∙ B. graded index ∙ C. step-index ∙ D. single mode
Last Answer : ∙ C. step-index
Description : The term single mode and multimode are best described as ∙ A. a number of fibers placed into fiber-optic cable ∙ B. the number of voice channels each fiber can support ∙ C. the number of wavelengths each fiber can support ∙ D. the index number
Last Answer : C. the number of wavelengths each fiber can support
Description : A single fiber can handle as many voice channels as ∙ A. a pair of copper conductors ∙ B. a 1500-pair cable ∙ C. a 500-pair cable ∙ D. a 1000-pair cable
Last Answer : B. a 1500-pair cable
Description : A single mode optical fiber has a core diameter of _____ nm. ∙ a. 0.1 ∙ b. 0.01 ∙ c. 0.2 ∙ d. 0.05
Last Answer : a. 0.1
Description : Under normal condition, a single fiber should not be used for a two-way communication mainly because of ∙ a. Loss ∙ b. Fading ∙ c. Noise ∙ d. Attenuation
Last Answer : ∙ c. Noise
Description : Which type of fiber-optic cable has the least modal dispersion? ∙ a. Single mode step-index ∙ b. Multimode step-index ∙ c. Single-mode graded-index ∙ d. Multimode graded-index
Last Answer : ∙ a. Single mode step-index
Description : Which type of fiber-optic cable is the best for very high speed data? ∙ a. Single-mode step-index ∙ b. Multimode step-index ∙ c. Single-mode graded-index ∙ d. Multimode graded-index
Last Answer : a. Single-mode step-index
Description : Which type of fiber optic cable is most widely used? ∙ a. Single-mode step-index ∙ b. Multimode step-index ∙ c. Single-mode graded-index ∙ d. Multimode graded-index
Description : Which of the following is not a common type of fiber-optic cable? ∙ a. Single-mode step-index ∙ b. Multimode graded-index ∙ c. Single-mode graded-index ∙ d. Multimode step-index
Last Answer : ∙ a. Single-mode step-index
Description : What type of fiber has the highest modal dispersion? ∙ a. Step-index multimode ∙ b. Graded index multimode ∙ c. Step-index single mode ∙ d. Graded index mode
Last Answer : a. Step-index multimode
Description : What is the insertion loss of connector-type splices for a single mode fiber optics? ∙ a. 0.51 dB ∙ b. 0.31 dB ∙ c. 0.49 dB ∙ d. 0.38 dB
Last Answer : d. 0.38 dB
Description : The Laser is a beam of radiations which are – (1) Non-coherent and monochromatic (2) Coherent and monochromatic (3) Non-coherent and non-monochromatic (4) Coherent and non-monochromatic
Last Answer : (2) Coherent and monochromatic Explanation: Laser, an acronym for Light Amplification by Stimulated Emission of Radiation, creates a radiation beam that is coherent (in-phase). In a coherent light ... results in a radiation beam of great intensity. It normally produces only one or two wavelengths.
Description : The Laser is a beam of radiations which are (1) Non-coherent and monochromatic (2) Coherent and monochromatic (3) Non-coherent and non-monochromatic (4) Coherent and non-monochromatic
Last Answer : Coherent and monochromatic
Description : The ratio of the speed of light in air to the speed of light in another substance is called ∙ A. speed factor ∙ B. index of reflection ∙ C. index of refraction ∙ D. speed gain
Last Answer : ∙ B. index of reflection
Description : The ratio of speed of light in air to the speed of light in another substance is called the ∙ a. Speed factor ∙ b. Index of reflection ∙ c. Index of refraction ∙ d. Dielectric constant
Last Answer : b. Index of reflection
Description : The loss in signal power as light travels down a fiber is called ∙ a. Dispersion ∙ b. Scattering ∙ c. Absorption ∙ d. Attenuation
Last Answer : ∙ d. Attenuation
Description : Refraction is the ∙ A. bending of light ∙ B. reflection of light waves ∙ C. distortion of light waves ∙ D. diffusion of light waves
Last Answer : A. bending of light
Description : The main benefit of light wave communications over microwaves or any other communications media are ∙ A. lower cost ∙ B. better security ∙ C. wider bandwidth ∙ D. freedom from interface
Last Answer : C. wider bandwidth
Description : EMD is best described by which statement? ∙ A. 70 percent of the core diameter and 70% of the fiber NA should be filled with light. ∙ B. 70 percent of the fiber diameter and 70% of the ... be measured at the output. ∙ D. 70 percent of the unwanted wavelengths should be attenuated by the fiber.
Last Answer : 70 percent of the core diameter and 70% of the fiber NA should be filled with light.
Description : The speed of light in plastic compared to the speed of light in air is ∙ A. less ∙ B. more ∙ C. the same ∙ D. zero
Last Answer : A. less
Description : The upper pulse rate and information-carrying capacity of a cable is limited by ∙ A. pulse shortening ∙ B. attenuation ∙ C. light leakage ∙ D. modal dispersion
Last Answer : D. modal dispersion
Description : Total internal reflection takes place if the light ray strikes the interface at an angle with what relationship to the critical angle? ∙ A. less than ∙ B. greater than ∙ C. equal to ∙ D. zero
Last Answer : ∙ B. greater than