Which capacitor type exhibits the smallest capacitance variation ____________?
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Answer: C. Silver plated mica capacitor
Explanation
Silver plated mica capacitors utilize stable mineral dielectrics and precision silver electrodes to prevent capacitance drift. Mica crystals possess a highly stable atomic lattice that resists physical deformation under varying temperature and humidity conditions. This exceptional material stability ensures minimal capacitance variation over long operating lifespans and temperature ranges. Silver plating applied directly to mica sheets creates intimate contact and eliminates air gaps that cause capacitance instability. Temperature coefficient metrics quantify how much a capacitor value changes when subjected to ambient thermal fluctuations. High precision electronic circuits require components with ultra low capacitance drift to maintain calibration accuracy.
Paper capacitors exhibit higher capacitance variation due to moisture absorption and degradation of the paper dielectric medium. Ceramic capacitors can experience significant capacitance changes across wide temperature ranges unless using stable Class materials. Stating none of the above is incorrect because silver plated mica capacitors explicitly provide superior stability.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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