3.12 DC Motor Generator

What factor primarily determines the strength of the voltage induced in the conductor of a generator?

• The length of the conductor
• The speed of the conductor's movement within the magnetic field
• The thickness of the conductor

When the loop in a simple generator is parallel to the magnetic lines of force, why is the induced voltage zero?

• The loop is cutting the lines of force at maximum rate
• The loop is not cutting any magnetic lines of force
• The magnetic field cancels out the voltage

How does armature reaction affect the brush position on the commutator?

• It causes the brushes to wear out faster
• It shifts the main field poles without a corresponding shift in brush positions
• It stabilizes the brush positions

What happens to the output voltage of a DC generator as the number of loops in the rotor is increased?

• The variation between maximum and minimum voltage values is reduced
• The output voltage varies more widely
• The output voltage becomes more unstable

How does armature reaction change with increasing generator load?

• Armature reaction decreases
• Armature reaction remains constant
• Armature reaction increases

What is one potential effect of armature reaction that directly impacts the commutator?

• Brush sparking on the commutator
• Increased commutator wear
• Enhanced commutator efficiency

Why do DC generators require a control circuit?

• To ensure the generator maintains the correct voltage and current
• To control the rotational speed of the armature
• To monitor the temperature of the generator

Which of the following is NOT a major component of a DC generator?

• Field frame
• Brush assembly
• Commutator

What is the role of the rotating armature in a DC generator?

• To produce magnetic flux
• To generate electrical energy by rotating within a magnetic field
• To maintain constant voltage output

What is the purpose of the brush assembly in a DC generator?

• To reduce electrical noise
• To transfer electrical current from the rotating armature to the external circuit
• To cool down the generator during operation