Neiep 600 Final Test Questions with Correct Answers

Neiep 600 Final Test Questions with Correct Answers In capacitors, what is the purpose of the dielectric? - Answer-Prevent arcing within the capacitor Which of the following is true about capacitors in AC circuits? - Answer-Current leads voltage all the time What describes a capacitor s ability to store an electrical charge? - Answer-Capacitance which of the following statements is correct about polarized electrolytic capacitors? - Answer-Voltage polarity must be correct What is the time constant for a circuit with 150k ohms and 2 microfarad capacitor? - Answer-.3 seconds If frequency is increased in a capacitave circuit what will happen? - Answer-Capacitive reactance will decrease What happens in a circuit, when the capacitor voltage equals the source voltage? - Answer-Current flow stops in the circuit In a DC circuit, which is correct about capacitors the instant when power is applied? - Answer-Current is maximum In the circuit shown in figure 1, what will be the total capacitance? - Answer-250 u(micro) farads If a circuit has a capacitor of 5 microfrauds and a source voltage of 120 volts DC through a resistance of 200k, how long will it take to fully charge? - Answer-5 seconds What happens in a circuit, when the capacitor voltage equals the source voltage? - Answer-Current flow stops in the circuit which statement best describes one time constant of a capacitor? - Answer-The time it takes to charge to 63.2% of applied voltage In a DC circuit, which is correct about capacitors the instant when power is applied? - Answer-Current is maximum If a circuit has a capacitor of 5 microfrauds and a source voltage of 120 volts DC through a resistance of 200k, how long will it take to fully charge? - Answer-5 seconds If two capacitors in parrallel have equal reactance of 40 ohms what is the total reactance? - Answer-20ohms Which of the following would increase the DC working voltage DCWV of a capacitor - Answer-Increase the plate area and the dielectric thickness Which statement is correct concerning capacitors? - Answer-Increased plate area, increases capacitance Which of the following is the unit used for measuring capacitance? - Answer-Farad Current flow from positive to negative is described as - Answer-conventional flow Current flow from negative to positive is called - Answer-electron flow By increases the distance between the plates we the charge capacity - Answer-decrease In AC circuits, DCWV should be times the RMS operating voltage of the circuit. - Answer-2 1/2 In DC circuits, DCWV should be times the RMs operating voltage of the circuit. - Answer-1 1/2 to 2 The type capacitor has a dielectric sandwich between two circular plates - Answer-Disc The capacitor uses a thin, oxide coating as a dielectric between the plates - Answer-Electrolytic The capacitor is polarity sensitive - Answer-Electrolytic The type capacitor uses less electronic real estate than other types. - Answer-Printed Circuit The final charge on a capacitor will equal the voltage - Answer-source Once a capacitor is charged and the circuit is opened, the charge will - Answer-Remain To discharge a capacitor safely use a resistor of - Answer-10k ohms Current leads voltage in a capacitive circuit - Answer-leads The time constant for a 200k ohms and 1 micro farad capacitor is - Answer-.2 seconds How much of the applied voltage will be on a capacitor at T3, if the source voltage is 25 volts - Answer-23.75 A leading cause of a relay contact failure is due to - Answer-arcing when a relay opens The capacitor will keep the voltage across the contacts below the point of ionization - Answer-true Noise suppression capacitors can be used to direct voltage flow to ground - Answer-spikes A capacitors opposition to changing is measured in ohms and is called - Answer- If frequency increases, then Xc - Answer-increases Two series capacitors with a reactance of 75 ohms and 183 ohms respectively, would have a combined reactance of ohms - Answer-258 ohms Two parallel capacitors with a reactance of 220 ohms each would have a combined reactance of ohms - Answer-110 ohms