MCQ in Fiber Optics Communications Part 4 | ECE Board Exam

This is the Multiple Choice Questions in Fiber Optics Communication Part 4 of the Series as one of the Electronics Systems and Technologies Examination topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Systems and Technologies scope, Electronics Communications Books, Journals and other Electronics Communications References.

MCQ Topic Outline included in ECE Board Exam Syllabi

• MCQ in Principles of Light Transmission
• MCQ in Types of Light Sources, Laser, LED
• MCQ in Light Detectors
• MCQ in Modulation and Waveform
• MCQ in System Design
• MCQ in General application
• MCQ in System Bandwidth
• MCQ in Splicing Techniques

Continue Practice Exam Test Questions Part 4 of the Series

Choose the letter of the best answer in each questions.

151. A device that was constructed from mirrors and selenium detectors that transmitted sound waves over a beam of light.

A. lightphone

B. photophone

C. cameraphone

D. walletphone

152. Which fiber-optic system is better?

A. 3 repeaters

B. 8 repeaters

C. 11 repeaters

D. 20 repeaters

153. 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

154. They were granted patents for scanning and transmitting television images through uncoated fiber cables.

A. Baird and Hansel

B. Bockham and Kao

C. Kapron and Keck

D. Maiman and Schawlow

155. The product of the bit rate and distance of a fiber-optic system is 2 Gbits-km/s. What is the maximum rate at 5 km?

A. 100 Mbits/s

B. 200 Mbits/s

C. 400 Mbits/s

D. 1000 Gbits/s

156. Approximately what is the frequency limit of the optical fiber?

A. 20 MHz

B. 1 MHz

C. 100 MHz

D. 40 GHz

157. 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

158. Photodiodes operate properly with

A. forward bias

B. reverse bias

C. neither forward nor reverse bias

D. either forward or reverse bias

159. He coined the term “fiber optics” in 1956.

A. Kapany

B. Kao

C. Bockham

D. Keck

160. They wrote a paper describing how it was possible to use stimulated emission for amplifying light waves (laser) as well as microwaves (maser).

A. Theodore Maiman

B. KC Kao and GA Bockham

C. Charles Townes and Arthur Schawlow

D. Kapron, Keck and Maurer

161. The scientist who built the first optical maser

A. Charles Townes

B. GA Bockham

C. Theodore Maiman

D. ACS Van Heel

162. 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

163. They proposed a new communication medium using cladded fiber cables.

A. Kao and Bockham

B. Maiman, Kao and Bockham

C. Kapron, Keck and Maurer

D. Maiman and Schawlow

164. An incident ray can be defined as

A. a light ray reflected from a flat surface

B. a light directed toward a surface

C. a diffused light ray

D. a light ray that happens periodically

165. Developed an optical fiber with losses less that 2 dB/km

A. Kao and Bockham

B. Maiman, Kao and Bockham

C. Maiman and Schawlow

D. Kapron, Keck and Maurer

166. The band of light frequencies that are too high to be seen by the human eye.

A. Ultraviolet

B. Visible light

C. Infrared

D. Yellow

167. Which of the following is the fastest light sensor?

A. PIN photodiode

B. Photovoltaic diode

C. Photodiode

D. Avalanche photodiode

168. Range of infrared

A. 360 nm to 440 nm

B. 670 nm to 10^3 nm

C. 110 nm to 240 nm

D. 770 nm to 10^6 nm

169. The term dispersion describes the process of

A. separating light into its component frequencies

B. reflecting light from a smooth surface

C. the process by which light is absorbed by an uneven rough surface

D. light scattering

170. The band of light frequencies to which human eye will respond

A. Infrared

B. Visible light

C. Ultraviolet

D. Cosmic ray

171. Laser light is very bright because it is

A. pure

B. white

C. coherent

D. monochromatic

172. Which of the following is the fastest light sensor?

A. PIN photodiode

B. Photovoltaic diode

C. Photodiode

D. Avalanche photodiode

173. Range of wavelength of visible light

A. 670 nm to 10^3 nm

B. 440 nm to 540 nm

C. 110 nm to 240 nm

D. 390 nm to 770 nm

174. The band of light frequencies that are too low to be seen by the human eye

A. Infrared

B. X-rays

C. Visible

D. Ultraviolet

175. Which of the following terms best describes the reason that light is refracted at different angles?

A. Photon energy changes with wavelength

B. Light is refracted as a function of surface smoothness

C. The angle is determined partly by a and b

D. The angle is determined by the index of the materials

176. Range of wavelengths of ultraviolet

A. 670 nm to 10^3 nm

B. 440 nm to 540 nm

C. 110 nm to 240 nm

D. 10 nm to 390 nm

177. Single frequency light is called

A. pure

B. intense

C. coherent

D. monochromatic

178. The coating in a fiber helps protect fiber from moisture, which reduces the possibility of the occurrence of a detrimental phenomenon called

A. static fatigue

B. mechanical fatigue

C. stress fatigue

D. coating fatigue

179. The term critical angle describes

A. the point at which light is refracted

B. the point at which light becomes invisible

C. the point at which light has gone from the refractive mode to the reflective mode

D. the point at which light has crossed the boundary layers from one index to another

180. 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

181. The three essential types of fiber commonly used today except:

A. Plastic core and cladding

B. Plastic core and glass cladding

C. Glass core and glass cladding (SCS)

D. Glass core and plastic cladding (PCS)

182. What phenomenon will result if the glass fiber is exposed to long periods of high humidity?

A. stress fatigue

B. core corrosion

C. stress corrosion

D. cladding corrosion

183. 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

184. Both LEDs and ILDs operate correctly with

A. forward bias

B. reverse bias

C. neither forward nor reverse bias

D. either forward or reverse bias

185. Any energy above the ground state is called ___________.

A. normal state

B. above-ground state

C. excited state

D. spontaneous state

186. The process of decaying from one energy level to another energy level is called __________.

A. Spontaneous emission

B. Excited emission

C. Absorption

D. Any of these

187. The process of moving from one energy level to another is called ____________.

A. Spontaneous emission

B. Excited emission

C. Absorption

D. Spontaneous decay

188. Most fiber optic light sources emit light in which spectrum?

A. visible

B. infrared

C. ultraviolet

D. X-ray

189. A packet of energy which is equal to the difference between the two energy levels.

A. Photons

B. Electronvolt

C. Quantum

D. Quanta

190. It is the science of measuring only light waves that are visible to the human eye.

A. Radiometry

B. Photometry

C. Ophthalmology

D. Optometry

191. The refractive index number is

A. a number which compares the transparency of a material with that of air

B. a number of assigned by the manufacturer to the fiber in question

C. a number which determines the core diameter

D. a term describing core elasticity

192. It is a science of measuring light throughout the entire electromagnetic spectrum

A. Radiometry

B. Photometry

C. Ophthalmology

D. Optometry

193. Which light emitter is preferred for high-speed data in a fiber-optic system?

A. incandescent

B. LED

C. neon

D. laser

194. Light intensity is generally described in terms of __________ and measured in _________.

A. Luminous flux density; Lumens per unit area

B. Luminous flux intensity; Lumens per unit area

C. Luminous flux density; Lumens per unit volume

D. Luminous flux intensity; Lumens per unit volume

195. In radiometric terms, it measures the rate at which electromagnetic waves transfer light energy

A. Optical radiation

B. Optical impedance

C. Optical illusion

D. Optical power

196. It is described as the flow of light energy past a given point in a specified time

A. Optical radiation

B. Optical impedance

C. Optical illusion

D. Optical power

197. 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

198. Optical power is sometimes called __________.

A. Radiant emission

B. Radiant power

C. Radiant flux

D. Radiant optics

199. In refraction that occurs in air/glass interfaces, among the visible light, which is bent the most?

A. red

B. violet

C. yellow

D. green

200. Fiber-optic cables with attenuation of 1.8, 3.4, 5.9 and 18 dB are linked together. The total loss is

A. 7.5 dB

B. 19.8 dB

C. 29.1 dB

D. 650 dB

Complete List of MCQ in Communications Engineering per topic