Which of the following substances fails to act as a dielectric material ?
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Answer: C. Rubber and polymeric resins
Explanation
Rubber and polymeric resins are widely used as electrical insulators and dielectric materials. These organic polymers prevent unwanted current leakage in various low-to-medium voltage electrical applications. Their molecular structure restricts free electron movement, classifying them as effective dielectric substances. Dielectric materials are electrical insulators that can be polarized by an applied electric field. Insulating polymers protect power cables and electronic components from catastrophic short-circuit failures. Material selection for electrical systems depends heavily on breakdown voltage and thermal stability.
Electrical engineers wrap copper wires in polymer coatings to ensure safe residential power distribution. Capacitors rely on solid dielectric films to store electrical energy efficiently within compact volumes. Industrial machinery requires robust rubber insulation to protect workers from severe electrical shock hazards. Cotton, silk, and paper have historically served as traditional fibrous dielectric materials in transformers. Asbestos, glass, porcelain, and mica are classic inorganic dielectrics known for high thermal resistance. All refractory materials are generally considered poor dielectrics or metallic oxides at elevated operating temperatures.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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