IOCL Junior Operator MCQ Part-8 || IOCL Junior Operator General Science Questions and Answers21. How does exposure to light affect rubber insulation?1 . Increases its dielectric strength 2 . Improves its moisture resistance 3 . Causes aging and degradation 4 . Enhances its flexibility Answer and SolutionAnswer: "Causes aging and degradation "Ultraviolet (UV) light causes rubber to degrade over time, leading to cracking and loss of its insulating properties. Discuss22. What are the key components mixed with pure rubber to produce Vulcanized Indian Rubber (VIR)?1 . Plasticizers and polymers 2 . Mineral matter and sulfur. 3 . Synthetic fibers and adhesives. 4 . Impregnated paper and varnish Answer and SolutionAnswer: "Mineral matter and sulfur. "VIR is created by adding Mineral matter (zinc oxide, red lead) and sulfur to pure rubber, which improves its properties through vulcanization. Discuss23. What percentage of sulfur is typically added to pure rubber during the VIR production process?1 . 1 to 2% 2 . 7 to 10% 3 . 15 to 20% 4 . 3 to 5% Answer and SolutionAnswer: "3 to 5% " 3 to 5% of sulfur is typically added to pure rubber during the VIR production process. The specific percentage of sulfur is crucial for achieving the desired vulcanization and material properties. Discuss24. What is the main advantage of VIR compared to pure rubber?1 . Greater mechanical strength 2 . Higher durability 3 . Water resistance 4 . All of the above Answer and SolutionAnswer: "All of the above "Vulcanization significantly enhances the physical and environmental resistance properties of rubber. Vulcanized Indian Rubber (VIR) is stronger and more durable than pure rubber. Greater Mechanical Strength: VIR can withstand more physical stress and pressure without breaking or deforming. Durability: It lasts longer and resists wear and tear better than pure rubber. Water Resistant: VIR is less likely to absorb water, which helps it maintain its insulating properties even in moist conditions. Discuss25. What is a significant disadvantage of VIR insulation?1 . Low dielectric strength 2 . Poor flexibility 3 . Sulfur reacts with copper conductors 4 . High manufacturing cost Answer and SolutionAnswer: "Sulfur reacts with copper conductors "The sulfur in VIR can corrode copper, making tinned conductors necessary. Discuss26. For what voltage levels is VIR insulation typically used?1 . High voltage cables 2 . Extra-high voltage cables. 3 . All voltage levels 4 . Low and moderate voltage cables Answer and SolutionAnswer: "Low and moderate voltage cables " VIR insulation typically used for low and moderate voltage cables. VIR is suitable for applications where voltage requirements are not extremely high, due to its properties and limitations. Discuss27. What is the primary material used to make impregnated paper insulation?1 . Chemically pulped paper from wood chippings 2 . Synthetic polymers 3 . Vulcanized rubber 4 . Varnished cotton cloth Answer and SolutionAnswer: "Chemically pulped paper from wood chippings "Impregnated paper insulation is made from wood pulp that is chemically processed and then impregnated with insulating compounds. Discuss28. What types of compounds are commonly used to impregnate paper insulation?1 . Paraffinic or naphthenic materials 2 . Metallic solutions 3 . Acids and alkalis 4 . Silicone oils Answer and SolutionAnswer: "Paraffinic or naphthenic materials "Paraffinic and naphthenic compounds are used because they provide good electrical insulation and moisture resistance to the paper. Discuss29. Which of the following is a key advantage of impregnated paper insulation?1 . High flexibility 2 . High temperature tolerance 3 . Excellent moisture resistance 4 . Low cost and high dielectric strength Answer and SolutionAnswer: "Low cost and high dielectric strength "Impregnated paper is favored for its cost-effectiveness and good electrical insulating properties, especially its high dielectric strength. Discuss30. What is a major disadvantage of impregnated paper insulation?1 . Low mechanical strength 2 . High manufacturing cost 3 . Hygroscopic nature 4 . Poor electrical conductivity Answer and SolutionAnswer: "Hygroscopic nature " Impregnated paper insulation is Hygroscopic in nature. The hygroscopic nature means the paper absorbs moisture, which can significantly reduce its insulation resistance. Discuss123456789
