Title: Servo Motor Test
Course: Basic of Motor Theory (IC 105-IC 105) > Section: Assessments

Q: A small DC motor uses a permanent magnet to develop the field flux. The motor would reverse direction of rotation if the power supply leads were reversed.
- True
- False
A: True

Q: A way to overcome resolution problems in a stepper motor is to.
- increase the step angle
- decrease the number of permanent magnets
- use microstepping
- increase the magnetic flux of the permanent magnets
A: increase the step angle

Q: BDCMs (Brushless DC Motors) have low maintenance requirements because they do not have brushes.
- True
- False
A: True

Q: If the sequence in which the stator poles are magnetized moves in a CCW direction, the rotor direction of a VR stepper motor will be  ______________.
- clockwise
- counterclockwise
A: clockwise

Q: In a BDCM, the ______________ is a permanent magnet.
- rotor
- stator
A: rotor

Q: In a brushless DC motor (BDCM), the field _____________.
- is stationary
- rotates
A: is stationary

Q: The __________ the number of poles used in a stepper motor, the better the resolution.
- smaller
- larger
A: smaller

Q: The amount of force required to move a rotor away from a held position is called.
- hysteresis
- holding torque
- magnetic flux
A: hysteresis

Q: The field strength in which the AC brushless servo motor winding is varied to control the speed or position of the rotor is ____________.
- auxiliary
- main
- both windings
A: auxiliary

Q: The moving coil motor (MCM) uses permanent magnet stators, a wound rotor armature, brushes and commutator, and it operates on the same principle as a permanent magnet DC motor.
- True
- False
A: True

Q: The reason why a wound armature PM motor has linear speed-torque characteristics is because there is no EMF induced into the field poles to cause the field strength to vary.
- True
- False
A: True

Q: The speed of a moving coil motor (MCM) is varied by ______________.
- changing the DC voltage applied to the armature
- changing the width of DC pulses applied to the armature
A: changing the DC voltage applied to the armature

Q: The stator flux of a permanent magnet motor is reduced when the rpm is increased due to CEMF.
- True
- False
A: False

Q: To stop the rotor in an AC brushless servo motor, ______________.
- the main field is turned off
- the output of the auxiliary winding drops to zero
- the auxiliary and main windings pulsate together
- the field around both the main and auxiliary windings are both stationary and at their maximum value
A: the main field is turned off

Q: To vary the speed of a moving coil motor (MCM), ___________ is varied.
- A DC voltage applied to the armature
- the width of square wave pulses applied to the armature
- the frequency of square wave pulses applied to the armature
A: A DC voltage applied to the armature