Difficulty: Easy
Correct Answer: True
Explanation:
Introduction / Context:“Alternator” is a foundational term in power engineering and automotive systems. Knowing precisely what an alternator is—and is not—ensures clarity when discussing generation, rectification, and system integration.
Given Data / Assumptions:
Concept / Approach:
An alternator is a synchronous AC generator: a rotating field (DC-excited or permanent magnet) induces AC in stationary stator windings. While automotive alternators include rectifier bridges to supply DC to the battery, the machine itself generates AC, confirming the definition in the statement.
Step-by-Step Solution:
Rotor field rotates at synchronous speed.Stator windings intercept time-varying flux → AC EMF is induced.Terminal AC may be directly used or rectified for DC loads.Verification / Alternative check:
Textbook classifications: DC generator vs. AC generator (alternator). Manufacturer datasheets refer to synchronous generators as alternators for AC output.
Why Other Options Are Wrong:
Claiming it produces DC conflates the machine with downstream rectification. Limiting to single-phase is wrong; alternators are commonly three-phase for power quality and efficiency.
Common Pitfalls:
Equating the electrical output after rectification (DC) with the machine type; always differentiate machine output from system-level conditioning.
Final Answer:
True.
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