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FCC General Exam Question Pool. Subelement 3BF.
Circuit Components. 1 Question.
--------------------------------------------------
3F 1.5 C
What is the effect of an increase in ambient temperature
on the resistance of a carbon resistor?
A. The resistance will increase by 20% for every 10
degrees centigrade that the temperature increases.
B. The resistance stays the same.
C. The resistance change depends on the resistor's
temperature coefficient rating.
D. The resistance becomes time dependent.
3F 2.6 D
What type of capacitor is often used in power
supplies to filter the rectified AC?
A. Disc ceramic.
B. Vacuum variable.
C. Mica.
D. Electrolytic.
3F 2.7 D
What kind of capacitors is used in power supply
circuits to filter transient voltage spikes
across the transformer secondary winding.
A. High value.
B. Trimmer.
C. Vacuum variable.
D. Supressor.
3F 3.5 C
How may inductors become Self-Resonant?
A. Through distributed electromagnetism.
B. Through eddy currents.
C. Through distributed capacitance.
D. Through parasitic hysteresis.
3F 4.1 A
What circuit component can change 120 VAC to 400 VAC ?
A. A transformer.
B. A capacitor.
C. A Diode.
D. An SCR.
3F 4.2 B
What is the source of energy connected to in a transformer?
A. To the secondary winding.
B. To the primary winding.
C. To the core.
D. To the plates.
3F 4.3 A
When no load is attached to the secondary winding of a
transformer, what is current in the primary winding called?
A. Magnetizing current.
B. Direct current.
C. Excitation current.
D. Stabilizing current.
3F 4.4 D
In what terms are the Primary and Secondary windings
of a power transformer usually specified?
A. Joules per Second.
B. Peak Inverse Voltage.
C. Coloumbs per Second
D. Volts or Volt-Amperes.
3F 5.1 C
What is the PEAK INVERSE VOLTAGE rating
of a power supply rectifier?
A. The highest transient voltage the diode will handle.
B. 1.4 time the AC frequency?
C. The maximum voltage to be applied
in the non-conducting direction.
D. 2.8 time the AC frequency.
3F 5.2 B
Why must silicon rectifier diodes be thermally protected?
A. Because of their proximity to the power transformer.
B. Because they will be destroyed if they become too hot.
C. Because of their susceptibility to transient voltages.
D. Because of their use in high-voltage applications.
3F 5.4 D
What are the two major ratings for silicon diodes
rectifiers of the type used in power supply curcuits
which must not be exceeded?
A. Peak Load Impedance; Peak Voltage.
B. Average Power; Average Voltage.
C. Capacitive Reactance; Avalanche Voltage.
D. Peak Inverse Voltage; Average Forward Current.
--------------------------------------------------
End of Subelement 3BF.