AC Theory 2 Unit 6

What type of current can have a changing amplitude? a. Alternating current b. Direct current c. All the above d. Neither of the above

All the above

Which value does not apply to a pure AC sine wave? a. Average b. Effective c. Peak d. RMS

average

Match the following terms to the correct definition. The full value of the AC sine wave measured from maximum positive to maximum negative.

The highest value measured from zero in either the positive or negative direction.

The measure of the effective value of the AC sine wave.

peak to peak

peak

root mean square

Determine if the following components are associated with AC generators, DC generators, or both.

Armature

Brushes

Commutator

Magnet Slip

Rings

both

both

dc

both

ac

Which component contains the coil(s) of wire in a revolving field generator? a. Brushes b. Commutator c. Rotor d. Stator

stator

Which component contains the magnet in a revolving field generator? a. Brushes b. Commutator c. Rotor d. Stator

rotor

Which generator type requires slip rings for connection to the external load circuit? a. Revolving armature b. Revolving field c. Both require slip rings d. Neither requires slip rings

revolving armature

Determine the relationship between each of the following and frequency.

Number of poles

Speed of rotation

both are directly proportional

Match the following terms to the correct definition.

A complete set of positive and negative values in a single sine wave.

Occurs when a wave crosses the reference line going either positive or negative.

The number of cycles that occur in one second.

The relationship between two waves of the same frequency.

The time required to complete one cycle.

Used to indicate the direction in which current flows in a circuit.

cycle

alternation

frequency

phase

period

polarity

Where is the voltage induced in an AC generator? a. Armature b. Field c. Rotor d. Stator

armature