Why are wire-wound resistors generally unsuited for high-frequency applications_______?
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Answer: D. exhibit unwanted inductive and capacitive effects
Explanation
Wire-wound resistors are constructed by winding resistive wire into helical coil shapes. Coiled wire naturally creates significant parasitic inductance and inter-turn capacitive effects. These unwanted reactive components distort high-frequency signals passing through the resistor. Parasitic inductance behaves like a series choke at high alternating current frequencies. Distributed capacitance forms between adjacent turns of the tightly wound wire helix. Non-inductive winding techniques attempt to cancel these parasitic effects by reversing winding directions.
Radio frequency circuits require carbon composition or metal film resistors instead of wire-wounds. High-speed digital transmission lines fail if excessive inductive components distort signal edges. Audio amplifiers use low-inductance resistors in feedback loops to prevent high-frequency oscillation. Electrical noise generation is primarily determined by material composition rather than coiling. Melting under excessive heat indicates power rating violations rather than high-frequency unsuitability. Power consumption remains determined by resistance value rather than high-frequency reactance.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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