Which of the following losses is/are present in every direct current generator armature? A. Winding copper loss B. Core eddy current loss C. Magnetic hysteresis loss D. All of the above.

Which of the following losses is/are present in every direct current generator armature? A. Winding copper loss B. Core eddy current loss C. Magnetic hysteresis loss D. All of the above.
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Answer: D  
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Last Answer : Ans: A Thinner the laminations, greater is the resistance offered to the induced e.m.f., smaller the current and hence lesser the I2R loss in the core.

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Last Answer : (A) Both eddy current and hysteresis losses decreases.

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Last Answer : Answer: C

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Last Answer : A) hysteresis losses is reduced

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Last Answer : A. Hysteresis loss

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Last Answer : D. Copper losses = iron losses

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Last Answer : (A) High resistance.

39 Which loss is not common between a transformer and rotating machines? A. Eddy current loss B. Copper loss C. Windage loss D. Hysteresis loss

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Last Answer : C. Reduce the eddy current losses

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The hysteresis and eddy current losses of a single phase transformer working on 200 V, 50 Hz

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No eddy current and hysteresis losses occur in

Last Answer : No eddy current and hysteresis losses occur in Electrostatic instruments.

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Basically, a magnetic amplifier is a saturable reactor with the addition of _____________. A. AC to the bias winding B. variable capacitance to all windings C. eddy current protectors D. a rectifier in the load circuit

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A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature

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Which of the following components are used to convert alternating current produced in the generator windings to direct current? A. Armature and equalizer B. Commutator and brushes C. Rotor and interpoles D. Field and exciter

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The purpose of the commutator and brushes on a DC generator is to _____________. A. transfer generated direct current voltage from the armature to the line B. convert the alternating voltage generated within the armature to a direct voltage C. provide a sliding contact method to excite the field D. reduce sparking between the armature and the carbon brushes

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