Chapter 12: Alternating Current
MULTIPLE CHOICE
1. Each time an AC generator moves through one complete revolution, it is said to complete one ____.
a.
cycle
c.
period
b.
alternation
d.
frequency
2. The ____ wave is the most basic and widely used of all the AC waveforms.
a.
sine
c.
triangular
b.
square
d.
sawtooth
3. ____ is the maximum departure of the value of an alternating current or wave from the average value.
a.
Amplitude
c.
Peak-to-peak value
b.
Peak value
d.
Effective value
4. The peak-to–peak value can be determined by ____ the peak values of the two alternations.
a.
multiplying
c.
subtracting
b.
dividing
d.
adding
5. In a square wave, the pulse width is equal to ____ the period.
a.
one-quarter
c.
double
b.
one-half
d.
triple
6. The ____ wave is useful as an electronic signal because its characteristics can be changed easily.
a.
sine
c.
triangular
b.
square
d.
sawtooth
7. The ____ waveform consists of positive and negative ramps of equal slope.
a.
sine
c.
triangular
b.
square
d.
sawtooth
8. In television sets and oscilloscopes, ____ waveforms are used to sweep the electron beam across the
screen, creating the image.
a.
sine
c.
triangular
b.
square
d.
sawtooth
9. ____ waveforms are composed of the fundamental frequency and all odd harmonics; the odd
harmonics are 180 degrees out of phase with the fundamental frequency.
a.
Sinusoidal
c.
Triangular
b.
Square
d.
Sawtooth
10. ____ waveforms are composed of both even and odd harmonics.
a.
Sinusoidal
c.
Triangular
b.
Square
d.
Sawtooth
COMPLETION
1. Maximum voltage is induced when the conductor is moved ____________________ to the lines of
flux.
2. The ____________________ of a sine wave is the absolute value of the point on the waveform with
the greatest amplitude.
3. The ____________________ of alternating current is the amount that produces the same degree of
heat in a given resistance as an equal amount of direct current.
SHORT ANSWER
1. Explain the relationship between frequency and period.
2. Describe the triangular waveform.
