Description : The ratio of the effective value of the counter EMF in volts, to the effective value of the current in amperes is called _____________. A. impedance factor B. capacitive reactance C. inductive reactance D. root mean square
Last Answer : Answer: C
Description : An AC circuit has capacitance arranged in series. If the line voltage remains constant, the capacitive reactance value can be varied by changing the _____________. A. line frequency B. resistance C. number of commutating poles D. number of interpoles
Last Answer : Answer: A
Description : An AC circuit has a capacitive reactance of 30 ohms in addition to an inductive reactance of 40 ohms connected in series. What is the reactance of the circuit? A. 8.37 ohms B. 10.00 ohms C. 50.00 ohms D. 70.00 ohms
Last Answer : Answer: B
Description : Decreasing the frequency in a capacitive circuit while maintaining a constant circuit voltage, will result in a/an _____________. A. increase in apparent power B. decrease in circuit current C. decrease in capacitive reactance D. decrease in total impedance
Description : AC circuits possess characteristics of resistance, inductance, and capacitance. The capacitive reactance of a circuit is expressed in _____________. A. ohms B. mhos C. henrys D. farads
Description : In series RLC circuit at resonant a) Voltage is in phase with current b) Current is maximum c) Inductive reactance = Capacitive reactance d) All of the above
Last Answer : Ans: All of the above
Description : AC circuits develop resistance, inductance, and capacitance. The inductive reactance of a circuit is expressed in _____________. A. ohms B. mhos C. henrys D. farads
Description : What is the reactance property at the input of a shorted quarter wavelength line? A. A parallel LC circuit B. A pure inductive reactance C. A series LC circuit D. A pure capacitive reactance
Last Answer : A. A parallel LC circuit
Description : When a megohmmeter is used to test insulation, the gradual rise of the pointer reading as a result of continued cranking, is caused by _____________. A. good conductor resistance B. the ... insulation C. the inductive reactance of the windings D. the dielectric-absorption effect of the insulation
Last Answer : Answer: D
Description : In an AC circuit, the inductive reactance of a coil varies with the _______________. A. resistance of the circuit B. frequency of the circuit C. voltage of the circuit D. current of the circuit
Description : Which of the following statements concerning AC circuits is correct? A. The power factor of a resistive circuit is always zero. B. True power in an inductive circuit always equals apparent power. ... . D. Total opposition to the flow of alternating current depends upon the amount of reactive power.
Description : Series capacitors are used to (a) compensate for line inductive reactance (b) compensate for line capacitive reactance (c) improve line voltage (d) none of the above
Last Answer : (a) compensate for line inductive reactance
Description : The electrical diagram shown in the illustration is used to depict a/an ____________. EL-0015 A. resistance circuit B. inductive circuit C. stepdown circuit D. capacitive circuit
Description : In AC Circuit Theory, the term that replaces the resistance is: w) inductance x) capacitance y) impedance z) reactance
Last Answer : ANSWER: Y -- IMPEDANCE
Description : The formula for computing impedance in a series circuit containing resistance, capacitance, and inductance is _____________. [ NOTE: the symbol * stands for 'multiplied by' ] A. Z = RT + XL + XC B. Z = R + XL - XC C. Z * Z = R * R + (XL - XC) * (XL - XC) D. Z = R * R + (XL * XC) - (XL * XC)
Description : Give equivalent resistance, reactance and impedance referred to secondary circuit.
Last Answer : Req = R2 +R1' = R2+ R1'/a² Xeq = X2 +X1' = X2+ X1'/a² Zeq = Z2 + Z1' = Z2+ Z1'/a² where a=T1/T2
Description : Give equivalent resistance, reactance and impedance referred to primary circuit.
Last Answer : Req = R1 +R2' = R1+a² R2' Xeq = X1 +X2' = X1+a² X2' Zeq = Z1 +Z2' = Z1+a² Z2' where a=T1/T2
Description : A series combination of resistance 100 ohm and capacitance 50µf is connected in series to a 230 V, 50HZ supply. Calculate (i) Capacitive reactance (ii) Current (iii) Power factor (iv) Power consumed
Last Answer : For RC series circuit
Description : In the illustrated circuit, one advantage of the capacitor coupling over direct coupling is ____________. EL-0048 A. as the frequency decreased the capacitive reactance (Xc) increases B. the amplifier becomes ... of the signal while it isolates the biasing of each stage. D. good frequency response.
Description : The component labeled 'CR1' in the circuit shown in the illustration __________________. EL-0085 A. varies its anode/cathode polarity depending on 'RL' current B. rectifies the varying voltage from the ... reactance to smooth ripple D. establishes a constant reference voltage for the base of 'Q1'
Description : Voltage will always lead current in a/an ______________. A. capacitive circuit B. inductive circuit C. magnetic circuit D. resistive circuit
Description : Define: (i) Inductive reactance (ii) Impedance.
Last Answer : i) Inductive reactance: Inductive reactance is the opposition offered by an inductor to alternating current . It is denoted by XL and given by XL = 2πf LΩ = ωL Ω ii)Impedance: It is the total opposition offered to flow of AC current in an AC circuit. It is denoted by Z and the unit is ohm.
Description : Known as the technique for adding a series inductor at or near the center of an antenna element in order to cancel the capacitive reactance of an antenna. A. Dipole B. Center loading C. Reflector D. loading coil
Last Answer : D. loading coil
Description : The purpose of the capacitor within component 'B' of the circuit shown in the illustration is to ____________. EL-0081 A. prolong the life of the component's contacts B. discharge the neon within ... the inductive reactance in the circuit D. store power to operate the circuit should 'D' open
Description : Arc in a circuit behaves as (a) a capackive reactance (b) an inductive reactance (c) a resistance increasing with voltage rise across the arc (d) a resistance decreasing with voltage rise across the arc
Last Answer : (d) a resistance decreasing with voltage rise across the arc
Description : Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop
Description : In a series-RLC circuit, what is the condition of the circuit if there is high impedance, low current, and low reactance voltages
Last Answer : Nonresonant (circuit is either above or below resonance)
Last Answer : In an R-C-L series circuit, during resonance, the impedance will be minimum.
Description : The hook-on AC volt-ammeter consists essentially of a split-core and a rectifiertype instrument connected to the secondary winding of a _____________. A. potential transformer B. control transformer C. current transformer D. reactance transformer
Description : When troubleshooting electronic equipment, you should use a high impedance multimeter ________________. A. to prevent excess current flow through the meter that would damage it B. for AC measurements only ... being tested D. so as not to load down the circuit and obtain erroneous voltage readings
Description : What is capacitance and capacitive reactance?
Last Answer : Capacitance The property of a capacitor to store electrical energy in it, when it is connected to an electric supply is called capacitance. Unit for measurement is farad. Capacitor store an electric ... called capacitive reactance and it denoted by the letter XC. The unit for measurement is ohm.
Description : The apparent power in a purely inductive circuit is also known as _____________. A. true power B. lead power C. induced power D. reactive power
Description : In preparing to take insulation resistance readings on a main generator, the windings should be grounded for about 15 minutes prior to the test to _____________. A. allow accurate zeroing of the meter ... the windings D. help the windings to cool to the same temperature as the ground test connection
Description : The total voltage of a series circuit is the _____________. A. sum of the individual voltage drops B. total resistance divided by the total current C. sum of the individual currents multiplied by the number of resistors D. total current divided by the total resistance
Description : What is the capacitive resistance of a 0.04 microfarad capacitor in ac circuit that has a frequency of 1000 hz?
Last Answer : The capacitive reactance is approximately 4 kΩ .
Description : In a series wound motor, the current passing through the field windings is also passing through the _____________. A. armature B. shunt field C. reactance comparator D. laminations
Description : When two generators are on the line and are sharing the load equally, they are said to be operating in _____________. A. frequency B. series C. parallel D. resonance
Description : On tank vessels with an electrically-driven capstan, the motor should be meggered periodically to test _____________. A. insulation resistance B. eddy currents C. capacitance D. armature reactance
Description : Although saturable reactors are extremely useful in some applications, their gain is low because of ____________. A. core hysteresis losses B. inductive reactance in the control winding C. IR drop throughout the load winding D. all of the above
Description : What is inductance and inductive reactance?
Last Answer : Inductance A coil carrying alternating current produces an alternating flux, which causes to link with same coil and produces an emf in the coil, which opposes the applied emf. This property is known ... is known as inductive reactance and denoted by the letter XL. The unit for measurement is ohm.
Description : In a series `LCR` circuit the frequency of a `10 V`, `AC` voltage soure is adjusted in such a fashion that the reactance of the inductor meausers `15
Last Answer : In a series `LCR` circuit the frequency of a `10 V`, `AC` voltage soure is adjusted in such a ... the series combination of `L` and `C`will be:
Description : Transmission lines when connected to antenna have A. capacitive load B. resistive load whose resistance is less than characteristics impedance C. resistive load at the resonant frequency D. resistive load whose resistance is greater than the characteristic impedance of the line
Last Answer : C. resistive load at the resonant frequency
Description : The unit of apparent power in a purely inductive circuit is called the _____________. A. kva B. var C. emf D. watt
Description : What is the formula for determining total reactance in a series circuit where the values of XC and XL are known?
Last Answer : X = XL – XC or X = XC - XL
Description : A megger is being used to test the insulation of an AC generator. The resistance value of a dry, clean winding will _____________. A. continue to rise as test potential is maintained, ... , becoming fairly steady after 5-7 minutes D. stabilize after approximately 2-4 minutes of fluctuation
Description : Give three point of difference between Resonance and Inductive effect.
Last Answer : Ans. Resonance: a. The resonance involves pi-electrons or lone pair of electrons. b. This effect moves all along the length of the conjugate system. c. This result in complete transfer ... become negligible from the fourth carbon atom onwards. c. This effect causes slight displacement of electrons.
Description : Phenol is acidic because of (a) Resonance (b) Electromeric effect (c) Inductive effect (d) Peroxide effect
Last Answer : Resonance
Description : Aryl halides are less reactive towards nucleophilic substitution as compared to alkyl halides due to (a) Inductive effect (b) Resonance stabilization (c) Tautomerism (d) Stereoisomerism
Last Answer : Resonance stabilization
Description : Compare series and parallel resonance on the basis of (i) Resonating frequency (ii) Impedance (iii) Current (iv) Magnification
Last Answer : S. No . Parameter Series Circuit Parallel Circuit 1 Resonating frequency 2 Impedance Minimum, Z = R Maximum, Z = L/CR 3 Current Maximum, I ... , I = V/(L/CR) 4 Magnification Voltage magnification takes place Current magnification takes place
Description : What is impedance and reactance diagram?
Last Answer : The impedance diagram is the equivalent circuit of power system in which the various components of power system are represented by their approximate equivalent circuits. The impedance diagram is ... ddiagram can be obtained from impedance diagram if all the resistive components are neglected.