Electric Motor

Front

In a DC motor, the armature turns and cuts through the lines of magnetic force produced by the _____. Options: field poles, brushes, commutator, rotor

Back

field poles

Front

What is TRUE regarding the neutral plane in a single-loop DC motor?

Back

No torque is produced in the neutral plane.

Front

The approximate horsepower of a 15,000W DC motor is

Back

20hp

Front

Which motor is best for adjustable speeds? Options: Shunt DC, Split-phase AC, Capacitor-start AC, Synchronous AC

Back

Shunt DC

Front

A polyphase synchronous motor has three stator windings that are _____.

Back

120° apart

Front

Which motor provides high starting torque and constant speed under load? Options: Brushless, Shunt, Series, Compound

Back

Compound

Front

The synchronous speed at which a four-pole, 50Hz induction motor operates is

Back

1,500 rpm

Front

For a given number of poles, what determines the speed of an AC motor? Options: Frequency, Current, Voltage, Frame size

Back

Frequency

Front

The speed of a three-phase squirrel cage induction motor is controlled by the frequency of the applied voltage and the _____. Options: diameter of the core, shaft length, number of poles, brush voltage.

Back

number of poles

Front

A wound-rotor induction motor is used _____?

Back

for speed control and to limit starting current