5
1-37. The current in the interpoles of a dc
motor is the same as the
1. armature current
2. field current
3. total load current
4. eddy current
1-38. In a dc motor, what is the purpose of the
resistor placed in series with the
armature?
1. To counteract armature reaction
2. To limit armature current
3. To increase field strength
4. To prevent overspeeding
1-39. Magnetic induction in an alternator is a
result of relative motion between what
two elements?
1. The rotor and the armature
2. The armature and the field
3. The field and the stator
4. The rotor and the field
1-40. Voltage is induced in what part of an
alternator?
1. The commutator
2. The brushes
3. The armature
4. The field
1-41. What are the two basic types of
alternators?
1. Multiphase and polyphase
2. Alternating current and direct current
3. Rotating field and rotating armature
4. Series-wound and shunt-wound
1-42. Which of the following alternator types
is most widely used?
1. Shunt-wound
2. Rotating-armature
3. Series-wound
4. Rotating-field
1-43. The purpose of the exciter in an
alternator is to
1. provide dc field excitation
2. compensate for armature losses
3. compensate for counter emf
4. counteract armature reaction
1-44. An alternator using a gas turbine as a
prime mover should have what type of
rotor?
1. Turbine-driven
2. Salient-pole
3. Armature
4. Geared
1-45. In alternators with low-speed prime
movers, only what type of rotor may be
used?
1. Geared
2. Armature
3. Salient-pole
4. Turbine-driven
1-46. Alternators are rated using which of the
following terms?
1. Volts
2. Watts
3. Amperes
4. Volt-amperes
1-47. What does the term single-phase mean
relative to single-phase alternators?
1. All output voltages are in phase with
each other
2. The voltage and current are in phase
3. The phase angle is constant
4. Only one voltage is produced
1-48. In a single-phase alternator with multiple
armature windings, how must the
windings be connected?
1. Series
2. Parallel
3. Wye
4. Delta
