GROL - Element 3 - Sub element C Questions With
Complete Solutions
3-19C1 What happens to the conductivity of photoconductive
material when light shines on it? Correct Answers It increases.
3-19C2 What is the photoconductive effect? Correct Answers
The increased conductivity of an illuminated semiconductor
junction.
3-19C3 What does the photoconductive effect in crystalline
solids produce a noticeable change in? Correct Answers The
resistance of the solid.
3-19C4 What is the description of an optoisolator? Correct
Answers An LED and a photosensitive device
3-19C5 What happens to the conductivity of a photosensitive
semiconductor junction when it is illuminated? Correct
Answers The junction resistance decreases.
3-19C6 What is the description of an optocoupler? Correct
Answers An LED and a photosensitive device.
3-20C1 What factors determine the capacitance of a capacitor?
Correct Answers Distance between the plates and the dielectric
constant of the material between the plates.
3-20C6 What is the purpose of a coupling capacitor? Correct
Answers It blocks direct current and passes alternating current.
, 3-21C1 A capacitor is sometimes placed in series with the
primary of a power transformer to: Correct Answers Improve
the power factor.
3-21C2 A transformer used to step up its input voltage must
have: Correct Answers More turns of wire on its secondary
than on its primary.
3-21C3 A transformer primary of 2250 turns connected to 120
VAC will develop what voltage across a 500-turn secondary?
Correct Answers 26.7 volts.
3-21C4 What is the ratio of the output frequency to the input
frequency of a single-phase full-wave rectifier? Correct
Answers 2:1.
3-21C5 A power transformer has a single primary winding and
three secondary windings producing 5.0 volts, 12.6 volts, and
150 volts. Assuming similar wire sizes, which of the three
secondary windings will have the highest measured DC
resistance? Correct Answers The 150 volt winding.
3-21C6 A power transformer has a primary winding of 200 turns
of #24 wire and a secondary winding consisting of 500 turns of
the same size wire. When 20 volts are applied to the primary
winding, the expected secondary voltage will be: Correct
Answers 50 volts.
3-22C1 In a linear electronic voltage regulator: Correct
Answers The conduction of a control element is varied in direct
proportion to the line voltage or load current.
Complete Solutions
3-19C1 What happens to the conductivity of photoconductive
material when light shines on it? Correct Answers It increases.
3-19C2 What is the photoconductive effect? Correct Answers
The increased conductivity of an illuminated semiconductor
junction.
3-19C3 What does the photoconductive effect in crystalline
solids produce a noticeable change in? Correct Answers The
resistance of the solid.
3-19C4 What is the description of an optoisolator? Correct
Answers An LED and a photosensitive device
3-19C5 What happens to the conductivity of a photosensitive
semiconductor junction when it is illuminated? Correct
Answers The junction resistance decreases.
3-19C6 What is the description of an optocoupler? Correct
Answers An LED and a photosensitive device.
3-20C1 What factors determine the capacitance of a capacitor?
Correct Answers Distance between the plates and the dielectric
constant of the material between the plates.
3-20C6 What is the purpose of a coupling capacitor? Correct
Answers It blocks direct current and passes alternating current.
, 3-21C1 A capacitor is sometimes placed in series with the
primary of a power transformer to: Correct Answers Improve
the power factor.
3-21C2 A transformer used to step up its input voltage must
have: Correct Answers More turns of wire on its secondary
than on its primary.
3-21C3 A transformer primary of 2250 turns connected to 120
VAC will develop what voltage across a 500-turn secondary?
Correct Answers 26.7 volts.
3-21C4 What is the ratio of the output frequency to the input
frequency of a single-phase full-wave rectifier? Correct
Answers 2:1.
3-21C5 A power transformer has a single primary winding and
three secondary windings producing 5.0 volts, 12.6 volts, and
150 volts. Assuming similar wire sizes, which of the three
secondary windings will have the highest measured DC
resistance? Correct Answers The 150 volt winding.
3-21C6 A power transformer has a primary winding of 200 turns
of #24 wire and a secondary winding consisting of 500 turns of
the same size wire. When 20 volts are applied to the primary
winding, the expected secondary voltage will be: Correct
Answers 50 volts.
3-22C1 In a linear electronic voltage regulator: Correct
Answers The conduction of a control element is varied in direct
proportion to the line voltage or load current.
