Which of these devices operates electromagnetically ?
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Answer: C. LVDT
Explanation
An LVDT operates using electromagnetic induction principles to measure physical linear displacement. It consists of a primary movable core and secondary coils excited by alternating magnetic fields. Core movement alters mutual inductance, generating an electrical output voltage proportional to position. Electromagnetic devices convert mechanical movement into electrical signals using magnetic fields. Faraday's law governs the voltage induced in the secondary coils of the transformer. LVDTs provide frictionless measurement, ensuring high reliability and extremely long operational lifespans.
Hydraulic cylinder position feedback in industrial manufacturing relies heavily on rugged LVDT sensors. Aerospace control surfaces use linear variable differential transformers for precise flight telemetry. Electromagnetic sensors operate reliably despite harsh industrial vibration and temperature conditions. Induction relays operate electromagnetically, but thermocouples generate voltages via thermal effects. Thermocouples convert temperature differences into voltages using the thermoelectric Seebeck effect. Option C is correct because the LVDT is the definitive electromagnetic displacement sensor.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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