Which of the enumerated devices operates on principles other than those of an electric motor ?
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Answer: D. Transformer
Explanation
A transformer operates on electromagnetic induction between stationary coils of wire. It transfers energy without creating mechanical rotation or kinetic movement. This distinguishes transformers from electromechanical devices like electric motors. Electromagnetic induction allows transformers to alter AC voltage levels statically. Electric motors convert electrical energy into mechanical torque through rotating armatures. Stationary core designs eliminate mechanical wear associated with rotating electrical machines.
Power distribution systems rely on transformers for efficient voltage stepping adjustments. Electrical engineering students learn to distinguish static inductive devices from rotating machines. Transformers provide vital electrical isolation between different sections of power networks. Galvanometers use motor principles with current carrying coils in magnetic fields. Ammeters operate on electromagnetic deflection principles shared with electric motors. Voltmeters utilize similar electromagnetic meter movements based on motor operation theory.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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