IOCL Junior Operator Electrical MCQ || IOCL Junior Operator General Science Questions and Answers21. What is the purpose of friction tape when used with rubber tape?1 . To increase insulation resistance 2 . To provide mechanical strength 3 . To replace rubber tape 4 . To enhance dielectric strength Answer and SolutionAnswer: "To provide mechanical strength "Friction tape adds mechanical strength over rubber tape, as rubber tape is not mechanically strong on its own. Discuss22. Which tape has high dielectric strength, is thin, and stretches to conform to contours?1 . Friction tape 2 . Rubber tape 3 . Varnished cambric tape 4 . Plastic tape (PVC tape) Answer and SolutionAnswer: "Plastic tape (PVC tape) "PVC tape offers high dielectric strength, flexibility, and thinness, making it versatile for insulation. Discuss23. What material is used to make friction tape?1 . Rubber 2 . Plastic 3 . Varnished cloth 4 . Cotton cloth impregnated with adhesive Answer and SolutionAnswer: "Cotton cloth impregnated with adhesive "Friction tape is made from cotton cloth treated with an adhesive. Discuss24. Varnished cambric tapes are ideal for insulating:1 . Low-voltage household wiring 2 . Temporary joints 3 . Motor connecting leads 4 . Underground cables Answer and SolutionAnswer: "Motor connecting leads "Varnished cambric tapes are designed for high-temperature applications like motor leads. Discuss25. What is the advantage of using a Megger for measuring insulation resistance?1 . It measures low resistance values accurately. 2 . It measures high resistance values without damaging insulation. 3 . It measures voltage drop. 4 . It measures current flow. Answer and SolutionAnswer: "It measures high resistance values without damaging insulation. "Meggers are designed to apply high voltage to measure high resistance without causing insulation breakdown. Discuss26. In stranded conductors, the size of individual conductors is specified in terms of:1 . Length 2 . Diameter 3 . Weight 4 . Color Answer and SolutionAnswer: "Diameter "The individual wires in a stranded conductor are measured by their diameter, typically in millimeters. Discuss27. What is the primary factor that determines the current carrying capacity of a cable?1 . Ambient temperature 2 . Number of cables in bunches 3 . Type of protection 4 . All of the above Answer and SolutionAnswer: "All of the above "The primary factor that determines the current carrying capacity of a cable are Type of conductors (metal) Type of insulation Cable run in conduit or in open surface Single or three phase circuit Type of protection – coarse or close excess current protection Ambient temperature Number of cables in bunches Length of circuit (permissible voltage drop) Discuss28. What type of cable insulation is particularly sensitive to high temperatures?1 . Rubber 2 . PVC 3 . Paper 4 . Varnished cambric Answer and SolutionAnswer: "PVC "PVC insulation can be damaged by temperatures exceeding its continuous operating limit, even for short periods. Discuss29. What is the key difference between coarse and close excess current protection?1 . The type of conductor used 2 . The ambient temperature 3 . The length of the cable 4 . The time it takes for the protection to operate Answer and SolutionAnswer: "The time it takes for the protection to operate "Coarse protection allows up to four hours at 1.5 times the load, while close protection operates within four hours at that load. Discuss30. Which device provides coarse excess current protection?1 . Fuses with a fusing factor exceeding 1.5 2 . Miniature circuit breakers (MCBs) 3 . Cartridge fuses 4 . Molded case circuit breakers (MCCBs) Answer and SolutionAnswer: "Fuses with a fusing factor exceeding 1.5 " Coarse protection devices allow a higher overload tolerance before tripping. Coarse protection allows up to four hours at 1.5 times the load, while close protection operates within four hours at that load. Discuss1234567
