Part C -LO5

An AC motor is a machine that converts:

• AC electrical energy to mechanical energy

• DC electrical energy to mechanical energy

• mechanical energy to DC electrical energy

• mechanical energy to AC electrical energy

AC motor's power is rated in terms of:

• Horsepower (Hp) or Watt

• Volt-Ampere (VA)

• Volt-Ampere reactive (VAR)

• Hertz (Hz)

Refer to the AC motor below, what is the name of the part of an AC motor labelled “B”?

• Rotor

• Stator

• Commutator

• Slip rings

Refer to the AC motor below, what is the name of the part of an AC motor “A”?

• Stator

• Rotor

• Commutator

• Slip rings

In the given AC motor nameplate data. What is the horsepower rating of the motor?

• 30

• 35

• 60

• 93

Mention the main two types of AC motors. 

• The induction motor and Synchronous motors 

• DC motors 

• Step motors and servo motors 

• HV motors

Which one of the following motors is considered an Asynchronous Motor

• Induction Motor

• Synchronous Motor

• DC motor

• Stepper motor

Which of the following best describes a synchronous motor? 

• The rotor speed is not equal to the rotating magnetic field speed

• It has multiple speed

• Rotor speed is equal to the rotating magnetic field speed

• Slip speed is at minimum 5%

What is the synchronous speed of a 2-pole synchronous motor supplied from a 50Hz supply?    

use the relationship N_S = 120 f / p

• 3000rpm

• 1500rpm

• 3600rpm

• 1800rpm

Why does a synchronous motor need another (usually a pony) motor?

• to bring the motor to synchronous speed at the start of the operation

• to provide more mechanical power

• to provide a connection to the shaft of another motor

• none of the choices