Underground Cable Question & AnswersJune 13, 2023 By Wat Electrical This article lists 75 Underground Cable MCQs for engineering students. All the Underground Cable Questions & Answers below include a hint and a link to the relevant topic wherever possible. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up on the fundamentals of the Underground Cable.Underground cables, also known as underground power lines or underground electrical cables, refer to electrical transmission or distribution cables that are installed below the ground surface. They are an alternative to overhead power lines, which are mounted on poles or towers. Underground cables are used for the transmission and distribution of electricity, telecommunications, and data signals. They are commonly used in urban areas, residential neighborhoods, commercial areas, and areas where overhead lines may not be feasible or desirable.Underground cables are typically made of electrical conductors, insulation materials, protective sheathing, and sometimes additional layers for added protection. The conductors are usually made of copper or aluminum and are insulated to prevent electrical leakage and short circuits.Overall, underground cables play a significant role in providing essential services such as electricity and communication, particularly in areas where overhead lines are impractical or undesirable. 1). What is the primary purpose of underground cables in electrical power distribution? Transmitting high-voltage power over long distances Providing a safer alternative to overhead power lines Minimizing electrical losses during transmission Facilitating easy maintenance and repairs None Hint2). Which of the following materials is commonly used as insulation for underground power cables? Copper Aluminum Polyethylene PVC (Polyvinyl Chloride) None Hint3). What is the purpose of metallic sheathing in underground cables? Providing additional mechanical strength Enhancing electrical conductivity Preventing moisture penetration Facilitating easier installation None Hint4). Which of the following statements about underground cables is true? Underground cables are more susceptible to lightning strikes compared to overhead lines Underground cables require more maintenance than overhead lines Underground cables have lower transmission capacity than overhead lines Underground cables are less affected by weather conditions compared to overhead lines None Hint5). What is the main disadvantage of underground power cables compared to overhead lines? Higher installation costs Greater environmental impact Increased transmission losses Limited voltage capacity None Hint6). Who is credited with the invention of the first practical underground cable? Alexander Graham Bell Samuel Morse Thomas Edison Michael Faraday None Hint7). The first underground cable was laid in which city? New York City London Paris Berlin None Hint8). In what year was the first underground cable laid? 1851 1876 1892 1905 None Hint9). The first underground cables were primarily used for which purpose? Telecommunications Electrical power transmission Internet connectivity Cable television None Hint10). The initial underground cables were made using which material? Copper Aluminum Steel Lead None Hint11). Who developed the first successful transatlantic telegraph cable? Thomas Edison Nikola Tesla Samuel Morse Cyrus West Field None Hint12). The first transatlantic telegraph cable was laid in what year? 1858 1872 1899 1923 None Hint13). Which company played a significant role in the development of underground cables during the late 19th century? General Electric AT&T Siemens IBM None Hint14). When did the first underground power cable system become operational? 1882 1901 1925 1940 None Hint15). The first underground power cables were made using which material? Rubber PVC Lead Aluminum None Hint16). Who is credited with the invention of the coaxial cable, widely used for television and data transmission? Alexander Graham Bell Oliver Heaviside John Logie Baird Clarence Hickman None Hint17). When was the first transcontinental telephone cable system in the United States completed? 1891 1911 1931 1951 None Hint18). What is the formula to calculate the capacitance of an underground cable? C = (2πεr) / ln(b/a) C = (ln(b/a)) / (2πεr) C = (2πεr) / (b – a) C = (b – a) / (2πεr) None Hint19). The formula for calculating the inductance of a three-core underground cable is _______________? L = (μ/2π) ln(b/a) L = (μ/2π) ln(a/b) L = (2πμ) ln(b/a) L = (2πμ) ln(a/b) None Hint20). Which formula is used to calculate the resistance of a single-core underground cable? R = ρL / (2πa) R = (2πa) / ρL R = (2πa) / Lρ R = Lρ / (2πa) None Hint21). The formula for calculating the reactance of an underground cable is ________________? X = ωL X = (2πfL) / ω X = ω / (2πfL) X = (2πfL) / ω^2 None Hint22). What is the formula to calculate the voltage drop in an underground cable? Vd = IZ Vd = IR Vd = IZcosθ Vd = IX None Hint23). The formula to calculate the power loss in an underground cable is _________________? Ploss = I^2R Ploss = I^2Z Ploss = I^2X Ploss = I^2R + I^2X None Hint24). The cable equation used to calculate the impedance is __________________? Z = R + jX Z = R – jX Z = R + jXL Z = R – jXL None Hint25). What does f represent in the cable equation X = 2πfL? Cable diameter Cable length Frequency of operation Cable insulation material None Hint26). The cable equation used to calculate the reactance is ________________? X = 2πfL X = 1/(2πfL) X = 2πfC X = 1/(2πfC) None Hint27). In the cable equation C = (2πε)/(ln(b/a)), what does ε represent? Cable diameter Cable length Cable insulation material Permittivity of the surrounding medium None Hint28). What is the most common cause of underground cable faults? Corrosion Overloading Physical damage Voltage fluctuations None Hint29). Which of the following is NOT a type of underground cable fault? Short circuit Open circuit Ground fault Voltage surge None Hint30). What equipment is commonly used to detect underground cable faults? Oscilloscope Megger Multimeter Earth fault locator None HintRead more about Multimeter31). Which type of fault occurs when two conductors come into contact with each other? Open circuit fault Short circuit fault Ground fault Induced fault None Hint32). What is the purpose of cable sheath bonding? To protect against lightning strikes To prevent unauthorized access To reduce electromagnetic interference To improve cable flexibility None Hint33). What is the typical insulation material used in underground cables? Rubber PVC (Polyvinyl chloride) XLPE (Cross-linked polyethylene) Fiberglass None Hint34). Which of the following is NOT a method of cable fault location? Time Domain Reflectometry (TDR) Thump testing Impulse generator Harmonic analysis None Hint35). What is the primary purpose of cable fault pre-location techniques? To pinpoint the exact fault location To assess the severity of the fault To determine the fault type To isolate the faulted section of the cable None Hint36). Which type of fault involves a connection between a conductor and the ground? Open circuit fault Short circuit fault Ground fault Induced fault None Hint37). What is the purpose of fault clearance in underground cable systems? To restore power supply quickly To prevent cable overheating To reduce the risk of fire To eliminate electromagnetic interference None Hint38). The parameter that determines the amount of power loss in an underground cable is _________________? Capacitance Resistance Inductance Conductance None Hint39). The parameter that determines the voltage drop in an underground cable is __________________? Capacitance Resistance Inductance Conductance None Hint40). The primary purpose of insulation in an underground cable is to __________________? Reduce power losses Increase the cable’s ampacity Provide mechanical protection Prevent leakage current None HintUnderground Cable MCQ for Exams41). The parameter that represents the ability of a cable to store electrical energy is __________________? Capacitance Resistance Inductance Conductance None Hint42). The parameter that represents the ability of a cable to oppose changes in current is _____________? Capacitance Resistance Inductance Conductance None Hint43). The unit of measurement for cable capacitance is _________________? Ohms (Ω) Farads (F) Henrys (H) Siemens (S) None Hint44). The unit of measurement for cable resistance is _______________? Ohms (Ω) Farads (F) Henrys (H) Siemens (S) None Hint45). The unit of measurement for cable inductance is __________________? Ohms (Ω) Farads (F) Henrys (H) Siemens (S) None Hint46). The parameter that causes power factor correction issues in underground cables is _______________? Capacitance Resistance Inductance Conductance None Hint47). The parameter that represents the leakage of current in an underground cable is _________________? Capacitance Resistance Inductance Conductance None Hint48). The skin effect in underground cables is most pronounced at ____________________? Low frequencies High frequencies DC (Direct Current) All frequencies equally None Hint49). What is one of the main advantages of underground cables? Lower installation costs Higher transmission efficiency Easier maintenance Faster fault detection None Hint50). Which of the following is a benefit of using underground cables in urban areas? Reduced visual impact Higher power capacity Lower voltage drop Easier access for repairs None Hint51). Which factor contributes to the improved reliability of underground cables? Reduced risk of lightning strikes Faster restoration after outages Easier identification of faults Lower overall costs None Hint52). What advantage do underground cables offer in terms of environmental impact? Reduced electromagnetic interference Lower carbon emissions Quicker installation time Simpler maintenance procedures None Hint53). Which aspect of underground cables helps in minimizing power outages caused by external factors? Enhanced insulation properties Efficient load balancing Redundant power sources Remote monitoring capabilities None Hint54). What advantage do underground cables provide during extreme weather conditions? Higher voltage capacity Greater resistance to mechanical damage Improved power quality Decreased installation time None Hint55). Which factor contributes to the longer lifespan of underground cables? Lower installation costs Reduced exposure to UV radiation Easier accessibility for repairs Faster fault detection None Hint56). Which advantage of underground cables is particularly beneficial in areas with high population density? Lower transmission losses Improved aesthetic appearance Reduced electromagnetic interference Quicker installation time None Hint57). What advantage do underground cables offer in terms of land use? Higher power capacity Reduced land acquisition requirements Easier installation on uneven terrain Quicker maintenance procedures None Hint58). What is one disadvantage of underground cables? High cost Easy maintenance Resistance to weather conditions Minimal environmental impact None Hint59). Which factor affects the underground cable’s cooling capability? Air circulation Temperature stability Weather conditions None of the above None Hint60). What can be a potential issue during repair or maintenance of underground cables? Easy accessibility Quick restoration of service Limited interference from external factors Difficulty in locating faults None HintUnderground Cable MCQ for Quiz61). Which of the following is a disadvantage of underground cables during expansion or modifications? Easy scalability Flexibility in routing Disruption of existing infrastructure Minimal impact on traffic None Hint62). What factor contributes to the longer downtime of underground cables compared to overhead cables? Faster fault detection Ease of repair Accessibility for maintenance personnel Difficulty in locating faults None Hint63). Which of the following is a disadvantage of underground cables in terms of electrical losses? Lower transmission losses Higher voltage stability Higher resistance losses Better power quality None Hint64). Which of the following can negatively impact the lifespan of underground cables? Weather conditions Increased insulation Enhanced protection from external factors None of the above None Hint65). What is a significant disadvantage of underground cables in terms of fault detection? Easy identification of faults Quick isolation of faulty sections Higher probability of faults Time-consuming fault location None Hint66). Which of the following is a drawback of underground cables in terms of system flexibility? Easy rerouting options Adaptability to changing needs Limited routing flexibility Ability to accommodate future technologies None Hint67). What type of underground cable is used for transmitting electrical power? Fiber optic cable Coaxial cable Power cable Twisted pair cable None Hint68). Which underground cable type is commonly used for high-speed internet connections? Power cable Coaxial cable Fiber optic cable Twisted pair cable None Hint69). What type of underground cable is used for telephone networks and Ethernet connections? Power cable Coaxial cable Fiber optic cable Twisted pair cable None Hint70). Which underground cable type is used for cable television and broadband internet? Power cable Coaxial cable Fiber optic cable Twisted pair cable None Hint71). What type of underground cable utilizes light pulses to transmit data? Power cable Coaxial cable Fiber optic cable Twisted pair cable None Hint72). Which type of communication cable is commonly used for transmitting data over long distances? Coaxial cable Fiber optic cable Twisted pair cable Ethernet cable None Hint73). Which type of communication cable is known for its immunity to electromagnetic interference (EMI)? Coaxial cable Fiber optic cable Twisted pair cable Ethernet cable None Hint74). Which type of communication cable is made up of two insulated copper wires twisted together? Coaxial cable Fiber optic cable Twisted pair cable Ethernet cable None Hint75). Which type of communication cable is commonly used for wired Ethernet connections? Coaxial cable Fiber optic cable Twisted pair cable Ethernet cable None HintFor More MCQsElectrical Cables Question & Answers Time's up
