What is capacitance and capacitive reactance?

What is capacitance and capacitive reactance?
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1 Answer

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 energy in the unit of charge and the unit of charge is coulomb.

Capacitive reactance
The opposition due to capacitance of capacitor in an electric circuit is called capacitive reactance and it denoted by the letter XC. The unit for measurement is ohm.
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Related questions

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 more efficient at lower capacitance. C. the arrangement allows the coupling of the signal while it isolates the biasing of each stage. D. good frequency response.

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.

Last Answer : Answer: C

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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

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Last Answer : Answer: A

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Last Answer : Answer: B

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Last Answer : Answer: B

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 collector of 'Q1' C. acts as a low capacitive reactance to smooth ripple D. establishes a constant reference voltage for the base of 'Q1'

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Description : What is the capacitive reactance across a point-contact diode as compared to a normal junction diode?

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Capacitive reactance formula

Description : Capacitive reactance

Last Answer : Capacitive reactance formula

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Description : Capacitive reactance is more when?

Last Answer : Capacitive reactance is more when capacitance is less and frequency of supply is less.

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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

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Description : What are the methods of capacitive switching?

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Description : The torque and current curves for a three-phase induction motor with a cage rotor, are shown in the illustration. Which of the following statements is true concerning the depicted curves? EL-0056 A. As slip ... D. If the motor is loaded to the point where 40% slip has resulted, it will stall.

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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

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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

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Last Answer : Answer: B

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

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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

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Tightly knit metal braid wire can be used with a printed circuit board when ___________. A. conductor flexibility is required B. desoldering components in the circuit C. electrically produced magnetic fluxes would cause inaccuracies in adjacent components D. reactance in the circuit must be kept to a minimum

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What Is Meant By Reactance Voltage?

Description : What Is Meant By Reactance Voltage?

Last Answer : An armature coil has certain self inductance. When coil undergoes commutation, there is change in current (di) in that coil and the commutation takes certain time(dt). Thus there is self-induced emf ... by L(di/dt). This EMF induced in the coil undergoing commutation is called reactance voltage.

Why synchronous generators are to be constructed with more synchronous reactance and negligible resistance?

Description : Why synchronous generators are to be constructed with more synchronous reactance and negligible resistance?

Last Answer : The presence of more resistance in the Synchronous generators will resist or oppose their synchronous operation. More reactance in the generators can cause good reaction between the two and help the ... to remain in synchronism in spite of any disturbance occurring in any one of the generators

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Description : What is synchronous reactance?

Last Answer : It is the combination of leakage reactance and armature reactance

How the leakage reactance of the transformer is reduced?

Description : How the leakage reactance of the transformer is reduced?

Last Answer : In transformers the leakage reactance is reduced by interleaving the high voltage and low voltage winding.

Give equivalent resistance, reactance and impedance referred to secondary circuit.

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

Give equivalent resistance, reactance and impedance referred to primary circuit.

Description : Give equivalent resistance, reactance and impedance referred to primary circuit.

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Description : Name any two methods of reducing short circuit current/ By providing neutral reactance.

Last Answer : By introducing a large value of shunt reactance between buses.