How does raising the field winding resistance impact the output voltage of a DC generator____________?
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Answer: B. decrease
Explanation
Raising the field winding resistance restricts the flow of field excitation current. Lower field current reduces the magnetic flux produced by the field poles. According to generator equations, less magnetic flux directly decreases the output voltage. Ohm's law dictates that higher resistance reduces current for a constant voltage source. Generated EMF is directly proportional to magnetic flux and rotational speed. Field rheostats allow operators to adjust output voltage by changing resistance.
Generator voltage regulators use variable resistance to control terminal voltage levels. Winding temperature increases resistance, causing slight drops in generator output voltage. Manual tuning of generator output relies on adjusting field circuit resistance values. Increase would violate basic electromagnetic induction and Ohm's law principles. Remain unaffected contradicts the direct dependency of flux on field resistance. Fluctuate heavily is incorrect because output voltage drops predictably and stably.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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