Forouzan Chapter 7 MCQ Flashcards
When the angle of incidence is ____________ the critical angle, the light beam bends along the interface.
A) less than C) more than
B) equal to D) none of the above
equal to
Transmission media lie below the __________ layer.
A) application C) network
B) transport D) physical
physical
_________ cable consists of an inner copper core and a second conducting outer sheath.
A) Twisted-pair C) Coaxial
B) Shielded twisted-pair D) Fiber-optic
Coaxial
__________ consists of a central conductor and a shield.
A) Twisted-pair C) Fiber-optic
B) Coaxial D) none of the above
Coaxial
. _______ cable can carry signals of higher frequency ranges than _______ cable.
A) Coaxial; twisted-pair C) Coaxial; fiber-optic
B) Twisted-pair; fiber-optic D) none of the above
Coaxial; twisted-pair
_________ are used for cellular phone, satellite, and wireless LAN communications.
A) Radio waves C) Microwaves
B) Infrared waves D) none of the above
Microwaves
The inner core of an optical fiber is _________ in composition.
A) copper D) liquid
B) glass or plastic D) liquid
glass or plastic
What is the major factor that makes coaxial cable less susceptible to noise than twisted-pair cable?
A) insulating material C) diameter of cable
B) inner conductor D) outer conductor
outer conductor
. Signals with a frequency below 2 MHz use _______ propagation.
A) line-of-sight C) ground
B) sky D) none of the above
ground
. In an optical fiber, the inner core is _________ the cladding.
A) less dense than C) the same density as
B) denser than D) another name for
denser than
________ cable consists of two insulated copper wires twisted together.
A) Twisted-pair C) Fiber-optic
B) Coaxial D) none of the above
Twisted-pair
In fiber optics, the signal is __________ waves.
A) radio C) infrared
B) light D) very low-frequency
light
Signals with a frequency above 30 MHz use _______propagation.
A) line-of-sight C) ground
B) sky D) none of the above
line-of-sight
A parabolic dish antenna is a(n) ___________ antenna.
A) unidirectional C) omnidirectional
B) bidirectional D) horn
unidirectional
A(n) _______ medium provides a physical conduit from one device to another.
A) unguided C) either (a) or (b)
B) guided D) none of the above
guided
. ________ cable is used for voice and data communications.
A) Twisted-pair C) Fiber-optic
B) Coaxial D) none of the above
Twisted-pair
Signals with a frequency between 2 MHz and 30 MHz use _______ propagation.
A) ground C) sky
B) line-of-sight D) none of the above
sky
Transmission media are usually categorized as ___________.
A) determinate or indeterminate C) guided or unguided
B) fixed or unfixed D) metallic or nonmetallic
guided or unguided
. ________ are used for short-range communications such as those between a PC and a peripheral device.
A) Radio waves C) Microwaves
B) Infrared waves D) none of the above
Infrared waves
. _________ media transport electromagnetic waves without the use of a physical conductor.
A) Guided C) Either (a) or (b)
B) Unguided D) None of the above
Unguided
________ cables are composed of a glass or plastic inner core surrounded by cladding, all encased in an outside jacket.
A) Twisted-pair C) Fiber-optic
B) Coaxial D) none of the above
Fiber-optic
Which of the following primarily uses guided media?
A) radio broadcasting C) local telephone system
B) satellite communications D) cellular telephone system
local telephone system
When a beam of light travels through media of two different densities, if the angle of incidence is greater than the critical angle, _______ occurs.
A) refraction C) criticism
B) reflection D) incidence
reflection
Which of the following is not a guided medium?
A) fiber-optic cable C) twisted-pair cable
B) coaxial cable D) atmosphere
atmosphere
Microwaves are _________.
A) omnidirectional C) unidirectional
B) bidirectional D) none of the above
unidirectional
________ cables carry data signals in the form of light.
A) Twisted-pair C) Fiber-optic
B) Coaxial D) none of the above
Fiber-optic
Radio waves are _________.
A) unidirectional C) bidirectional
B) omnidirectional D) none of the above
omnidirectional
In a fiber-optic cable, the signal is propagated along the inner core by __________.
A) refraction C) modulation
B) reflection D) none of the above
reflection
