recap the previous session. 3

An electric generator is a machine that uses ________ to convert mechanical energy into electric energy.

• magnetism

• watts

• amps

• volts

The device that provides the mechanical energy input to a generator is called the

• prime mover

• rotor

• stator

• armature

An electric motor uses _________ to operate.

• electric current

• heat

• magnetism

• electric current and magnetism

Generators operate on the principle that a voltage is induced in a conductor whenever the conductor is _______ a magnetic field so as to cut lines of force.

• placed in

• seen in

• moved through

• conducted in

Torque is best defined as:

•   the change in motor speed due to armature reaction

•   the turning force produced by a motor

• the difference between the no-load and full-load speed of a motor

•   the opposing force produced in a motor’s armature.

Which of the following is not a requirement for motor action?

• An external source of voltage

• A magnetic field

• A source of mechanical energy

• A conductor

The purpose of a commutator on a DC motor is

• to change AC to DC.

• to adjust the speed of the motor.

• to maintain the proper direction of current flow in the armature conductors.

• to adjust the torque of the motor.

The two basic categories of motors are

• low and high torque

• AC and DC

• less and more than 1 HP

• low and high speed

One advantage DC type motors have over AC types is that

• they use a more common type of voltage source

• their speed can be easily varied

• they require less maintenance

• they are less expensive to manufacture

Which of the following is not a rotary part in the DC motor

• Rotor.

• Slip rings.

• Commutator.

• Field Winding.