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resistance is real, the other purely imaginary.
AnswerResistance is the opposition to the flow of current (AC or DC) which is proportional to a conductor's cross-sectional area and resistivity, and inversely proportional to its length. Reactance is the opposition to AC current due to either the circuit's inductance or its capacitance, and are termed inductive reactance and capacitive reactance. Resistance and reactance are both measured in ohms.
Inductive reactance is proportional to the circuit's inductance and the frequency of the supply; capacitive reactance is inversely proportional to the circuit's capacitance and the frequency of its supply. In other words, inductive reactance increases with frequency, whereas capacitive reactance decreases with frequency.
All AC circuits contain resistance, and most contain some degree of inductance and/or capacitance. So the opposition offered by a circuit to AC current includes resistance together with some combination of inductive and/or capacitive reactance.
It's incorrect to suggest that reactance is 'imaginary'in the every day sense of the word -it exists, so it must be 'real'. In this context, 'imaginary' is a mathematical term that indicates that if resistance and reactance were represented in a vector diagram (called an 'impedence diagram'), then reactance quantity would lie at right-angles to the resistance quantity. For this reason, the overall opposition to current flow, which is called impedance, is not the algebraic sum of resistance and reactance, but the vector sum of the two. So, for example, if a circuit had a resistance of, say, 4 ohms, and its inductive reactance was 3 ohms, then its impedance would be 5 ohms -not 7 ohms.
Although we can represent resistance and reactance using a vector diagram (impedance diagram), strictly-speaking the quantities themselves are not vector quantities. The impedance diagram is created as a result of a phasor (vector) diagram representing the current and voltage relationships in the AC circuit.
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Beau'Inductance (symbol: L), expressed in henrys (symbol; H), is the property of a circuit that opposes any change in current. Inductive reactance (symbol: XL) is the opposition to a.c. current, expressed in ohms, due to the inductance of a circuit and the frequency of the supply.
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What does capacitive reactance oppose?
Inductive reactance.
What is the symbol for inductive reactance?
Inductive reactance does NOT have it own sign or symbol. Rather, it uses Ohms as a quantifier. But Capacitive reactance ALSO uses Ohms as a quantifier. Fortunately, 1 Ohm of Inductive reactance is cancelled by 1 Ohm of Capacitive reactance at the same frequency of measurement.
Why is capacitive voltage higher than inductive voltage in an R-L-C circuit?
It isn't necessarily so. The capacitive voltage is the product of the current and capacitive reactance, while the inductive voltage is the product of the current and the inductive reactance. So it depends whether the capacitive reactance is greater or smaller than the inductive reactance!
Can inductive reactance be in kilo ohm?
Yes. Inductive and capacitive reactance is measured in ohms, and it is entirely possible for reactance to be greater than 1,000, or even 1,000,000, ohms. It all depends on frequency.
What is meant by susceptance in electrical engineering?
Susceptance is the reciprocal of reactance, and is expressed in siemens (symbol: S). So, inductive susceptanceis the reciprocal of inductive reactance, and capacitive susceptance is the reciprocal of capacitive reactance.
