% FILENAME = N9.TXTR % Capacitors, Inductors, Resonance % Release version 2, January 2000 % Q 3 deleted "radio" 6 Mar 2012. PDF is corrected already %Question: 1 #9.1 The total capacitance of two or more capacitors in series is: always less than that of the smallest capacitor always greater than that of the largest capacitor found by adding each of the capacitances together found by adding the capacitances together and dividing by their total number % ans 1 %Question: 2 #9.2 Filter capacitors in power supplies are sometimes connected in series to: withstand a greater voltage than a single capacitor can withstand increase the total capacity reduce the ripple voltage further resonate the filter circuit % ans 1 %Question: 3 #9.3 A component is identified as a capacitor if its value is measured in: microvolts millihenrys megohms microfarads % ans 4 %Question: 4 #9.4 Two metal plates separated by air form a 0.001 uF capacitor. Its value may be changed to 0.002 uF by: bringing the metal plates closer together making the plates smaller in size moving the plates apart touching the two plates together % ans 1 %Question: 5 #9.5 The material separating the plates of a capacitor is the: dielectric semiconductor resistor lamination % ans 1 %Question: 6 #9.6 Three 15 picofarad capacitors are wired in parallel. The value of the combination is: 45 picofarad 18 picofarad 12 picofarad 5 picofarad % ans 1 %Question: 7 #9.7 Capacitors and inductors oppose an alternating current. This is known as: resistance resonance conductance reactance % ans 4 %Question: 8 #9.8 The reactance of a capacitor increases as the: frequency increases frequency decreases applied voltage increases applied voltage decreases % ans 2 %Question: 9 #9.9 The reactance of an inductor increases as the: frequency increases frequency decreases applied voltage increases applied voltage decreases % ans 1 %Question: 10 #9.10 Increasing the number of turns on an inductor will make its inductance: decrease increase remain unchanged become resistive % ans 2 %Question: 11 #9.11 The unit of inductance is the: farad henry ohm reactance % ans 2 %Question: 12 #9.12 Two 20 uH inductances are connected in series. The total inductance is: 10 uH 20 uH 40 uH 80 uH % ans 3 %Question: 13 #9.13 Two 20 uH inductances are connected in parallel. The total inductance is: 10 uH 20 uH 40 uH 80 uH % ans 1 %Question: 14 #9.14 A toroidal inductor is one in which the: windings are wound on a closed ring of magnetic material windings are air-spaced windings are wound on a ferrite rod inductor is enclosed in a magnetic shield % ans 1 %Question: 15 #9.15 A transformer with 100 turns on the primary winding and 10 turns on the secondary winding is connected to 230 volt AC mains. The voltage across the secondary is: 10 volt 23 volt 110 volt 2300 volt % ans 2 %Question: 16 #9.16 An inductor and a capacitor are connected in series. At the resonant frequency the resulting impedance is: maximum minimum totally reactive totally inductive % ans 2 %Question: 17 #9.17 An inductor and a capacitor are connected in parallel. At the resonant frequency the resulting impedance is: maximum minimum totally reactive totally inductive % ans 1 %Question: 18 #9.18 An inductor and a capacitor form a resonant circuit. The capacitor value is increased by four times. The resonant frequency will: increase by four times double decrease to half decrease to one quarter % ans 3 %Question: 19 #9.19 An inductor and a capacitor form a resonant circuit. If the value of the inductor is decreased by a factor of four, the resonant frequency will: increase by a factor of four increase by a factor of two decrease by a factor of two decrease by a factor of four % ans 2 %Question: 20 #9.20 A "high Q" resonant circuit is one which: carries a high quiescent current is highly selective has a wide bandwidth uses a high value inductance % ans 2