Resistance
resistance is the opposition to the flow of electric charge
In the simplest case, that would be resistance - but there is also another type of opposition (only relevant for AC) called reactance. The combined effect of resistance and reactance is called impedance.
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.
Answer: Inductive reactance is the opposition to the change in current in an electrical circuit and is abbreviated Xl. Answer: The opposition to current flow is called resistance (for DC), or impedance (for AC; often just called resistance); the unit for both is the ohm.
The resistance of an a.c. load is called 'resistance' (R). Resistance is not affected by frequency, only by the cross-sectional area, length, and resistivity of the conductor. Having said that, because of the skin effect, which causes an a.c. current to flow closer to the surface of the conductor, the effective cross-sectional are is reduced, so the value of a.c resistance is somewhat higher than the d.c. resistance -this difference increases with frequency.The opposition to a.c due to inductive or capacitive loads is called reactance (inductive reactance or capacitive reactance), and the overall opposition to a.c. current is the vector sum of resistance and reactance, and is called impedance. That is:(impedance)2 = (resistance)2 + (reactance)2
Impedance.
"Opposition to current" can refer to resistance, reactance, or impedance.
resistance is the opposition to the flow of electric charge
In the simplest case, that would be resistance - but there is also another type of opposition (only relevant for AC) called reactance. The combined effect of resistance and reactance is called impedance.
current - movement of electrical chargesvoltage - electrical force/pressurepower - work doneresistance - opposition to currentinductive reactance - opposition to changes in currentcapacitive reactance - opposition to changes in voltagetotal impedance - vector sum of resistance, inductive reactance, and capacitive reactanceetc.
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.
Capacitive reactance.
Answer: Inductive reactance is the opposition to the change in current in an electrical circuit and is abbreviated Xl. Answer: The opposition to current flow is called resistance (for DC), or impedance (for AC; often just called resistance); the unit for both is the ohm.
The resistance of an a.c. load is called 'resistance' (R). Resistance is not affected by frequency, only by the cross-sectional area, length, and resistivity of the conductor. Having said that, because of the skin effect, which causes an a.c. current to flow closer to the surface of the conductor, the effective cross-sectional are is reduced, so the value of a.c resistance is somewhat higher than the d.c. resistance -this difference increases with frequency.The opposition to a.c due to inductive or capacitive loads is called reactance (inductive reactance or capacitive reactance), and the overall opposition to a.c. current is the vector sum of resistance and reactance, and is called impedance. That is:(impedance)2 = (resistance)2 + (reactance)2
There is pure resistance, inductive reactance, and capacitive reactance.
The load current will lag the supply voltage by an angle called a 'phase angle', determined by the values of resistance and inductive reactance. The magnitude of the load current will be determined by the impedance of the circuit, which is the vector sum of the resistance and inductive reactance.
Assuming you are talking about an AC circuit, then the total opposition to the flow of current in an R-C circuit is called its impedance (symbol: Z), measured in ohms. This is the vector sum of the circuit's resistance (R) and its capacitive reactance (XC) -each also measured in ohms.