G6 - CIRCUIT COMPONENTS [3 Exam Questions 3 Groups] Flashcards
Which of the following is an important characteristic for capacitors used to filter the DC output of a switching power supply?
A. Low equivalent series resistance
B. High equivalent series resistance
C. Low Temperature coefficient
D. High Temperature coefficient
A. Low equivalent series resistance
Which of the following types of capacitors are often used in power supply circuits to filter the rectified AC?
A. Disc ceramic
B. Vacuum variable
C. Mica
D. Electrolytic
D. Electrolytic
Which of the following is an advantage of ceramic capacitors as compared to other types of capacitors?
A. Tight tolerance
B. High stability
C. High capacitance for given volume
D. Comparatively low cost
D. Comparatively low cost
Which of the following is an advantage of an electrolytic capacitor?
A. Tight tolerance
B. Non-polarized
C. High capacitance for given volume
D. Inexpensive RF capacitor
C. High capacitance for given volume
Which of the following is one effect of lead inductance in a capacitor used at VHF and above?
A. Effective capacitance may be reduced
B. Voltage rating may be reduced
C. ESR may be reduced
D. The polarity of the capacitor might become reversed
A. Effective capacitance may be reduced
What will happen to the resistance if the temperature of a resistor is increased?
A. It will change depending on the resistor�s reactance coefficient
B. It will stay the same
C. It will change depending on the resistor’s temperature coefficient
D. It will become time dependent
C. It will change depending on the resistor’s temperature coefficient
Which of the following is a reason not to use wire-wound resistors in an RF circuit?
A. The resistor’s tolerance value would not be adequate for such a circuit
B. The resistor’s inductance could make circuit performance unpredictable
C. The resistor could overheat
D. The resistor’s internal capacitance would detune the circuit
B. The resistor’s inductance could make circuit performance unpredictable
Which of the following describes a thermistor?
A. A resistor that is resistant to changes in value with temperature variations
B. A device having a specific change in resistance with temperature variations
C. A special type of transistor for use at very cold temperatures
D. A capacitor that changes value with temperature
B. A device having a specific change in resistance with temperature variations
What is an advantage of using a ferrite core toroidal inductor?
A. Large values of inductance may be obtained
B. The magnetic properties of the core may be optimized for a specific range of frequencies
C. Most of the magnetic field is contained in the core
D. All of these choices are correct
D. All of these choices are correct
How should the winding axes of solenoid inductors be placed to minimize their mutual inductance?
A. In line
B. Parallel to each other
C. At right angles
D. Interleaved
C. At right angles
Why would it be important to minimize the mutual inductance between two inductors?
A. To increase the energy transfer between circuits
B. To reduce unwanted coupling between circuits
C. To reduce conducted emissions
D. To increase the self-resonant frequency of the inductors
B. To reduce unwanted coupling between circuits
What is a common name for an inductor used to help smooth the DC output from the rectifier in a conventional power supply?
A. Back EMF choke
B. Repulsion coil
C. Charging inductor
D. Filter choke
D. Filter choke
What is an effect of inter-turn capacitance in an inductor?
A. The magnetic field may become inverted
B. The inductor may become self resonant at some frequencies
C. The permeability will increase
D. The voltage rating may be exceeded
B. The inductor may become self resonant at some frequencies
What is the peak-inverse-voltage rating of a rectifier?
A. The maximum voltage the rectifier will handle in the conducting direction
B. 1.4 times the AC frequency
C. The maximum voltage the rectifier will handle in the non-conducting direction
D. 2.8 times the AC frequency
C. The maximum voltage the rectifier will handle in the non-conducting direction
What are two major ratings that must not be exceeded for silicon diode rectifiers?
A. Peak inverse voltage; average forward current
B. Average power; average voltage
C. Capacitive reactance; avalanche voltage
D. Peak load impedance; peak voltage
A. Peak inverse voltage; average forward current
What is the approximate junction threshold voltage of a germanium diode?
A. 0.1 volt
B. 0.3 volts
C. 0.7 volts
D. 1.0 volts
B. 0.3 volts
When two or more diodes are connected in parallel to increase current handling capacity, what is the purpose of the resistor connected in series with each diode?
A. To ensure the thermal stability of the power supply
B. To regulate the power supply output voltage
C. To ensure that one diode doesn’t carry most of the current
D. To act as an inductor
C. To ensure that one diode doesn’t carry most of the current
What is the approximate junction threshold voltage of a conventional silicon diode?
A. 0.1 volt
B. 0.3 volts
C. 0.7 volts
D. 1.0 volts
C. 0.7 volts