The plot of current vs. frequency is not symmetric because the equations for inductive reactance and capacitive reactance are not symmetric. One is linear and the other is inverse.
Answer:A given combination of R,L and C in series allows the current to flow in a certain frequency range only.For this reason it is known as an acceptor circuit i.e.,it accepts some specific frequencies....
THE PARALLEL rlc CIRCUIT IS CALLED A REJECTOR CIRCUIT BECAUSE IT REJECTS DOWN THE CURRENT. THE REASON IS AT RESONANCE THE IMPEDENCE OF THE CAPACITOR BECOMES EQUAL TO THAT OF THE INDUCTOR SO NO CURRENT FLOWS. AT LOW FREQUENCY THE CAPACITIVE REACTANCE IS LOW SO ALL THE CURRENT FLOWS THROUGH THE INDUCTOR AND WHEN THE FREQUENCY IS HIGH ALL THE CURRENT WILL FLOW THROUGH THE CAPACITOR BECAUSE AT THAT POINT THE REACTANCE OF THE CAPACITOR IS LOW. SO WE OBTAIN A V-SHAPED GRAPH WITH THE PEAK OF V INDICATING THE REJECTION OF CURRENT.
A series resonant circuit is one in which the inductive and capacitive reactance are equal in magnitude. Since the signs of the vectors of their reactance are opposite, they cancel and so leave only the resistance of the series circuit at the resonant frequency. Because reactance of a capacitor is inversely related to frequency, and the reactance of an inductor is directly related to frequency, this happens at a particular frequency dependent on the values of capacitance and inductance. You see, when you apply a sine wave to an inductor, the current lags behind the voltage by 90 degrees. Or you may look at it as the voltage leading the current by 90 degrees. But when a sine wave is applied to a capacitor, the reverse is true. Current leads voltage by 90 degrees. Or voltage lags behind current by 90 degrees. Put a capacitor and inductor in series and input a sine wave of current at the frequency at which both have the same amount of reactance. Current is equal in magnitude and phase everywhere in a series circuit. Voltage dropped across the inductor is 90 degrees ahead of the current, while voltage dropped across the capacitor is 90 degrees behind the current. This puts the voltage drops 180 degrees out of phase with each other. Because the applied frequency is the one at which the reactance of each component is equal in magnitude, the voltage drops are also equal in magnitude so they sum to zero volts. Zero volts at any current is zero ohms (Ohm's law, R = E/I). In the real world, both parts have resistance or a series resistor may be part of the design. But the end result is that impedance of the series circuit is lowest at the resonant frequency.
when the frequency is increased the total impedance of a series RC circuit is decrease.
The frequency of the power waveform in a capacitive circuit, or for that matter, an inductive circuit, is the same as the input voltage or current. Its just that the current leads the voltage (capacitor) or lags the voltage (inductor) by a phase angle, the cosine of which is the power factor. It does not matter how many sine waves you have, or what their phase angle is; if they all have the same frequency, the resultant, by Fourier analysis, is still a sine wave of the same frequency.
As a parallel resonance circuit only functions on resonant frequency, this type of circuit is also known as an Rejecter Circuit because at resonance, the impedance of the circuit is at its maximum thereby suppressing or rejecting the current whose frequency is equal to its resonant frequency.
Current is at maximum
because at resonance frequency in LRC parallel circuit,impedance is high, so it minimize the current. thus we say its a rejector circuit .
Because the series resonant circuit has the lowest possible impedance at resonance frequency, thus allowing the AC current to circulate through it. At resonance frequency, XC=XL and XL-XC = 0. Therefore, the only electrical characteristic left in the circuit to oppose current is the internal resistance of the two components. Hence, at resonance frequency, Z = R. Note: This effect is probably better seen with vectors. Clarification: Resonant circuits come in two flavors, series and parallel. Series resonant circuits do have an impedance equal to zero at the resonant frequency. This characteristic makes series resonant circuits especially well suited to be used as basic pass-band filters (acceptors). However, parallel circuits present their maximum impedance at the resonant frequency, which makes them ideal for tuning purposes.
Series resonant circuits have their lowest impedance at the resonant frequency. Parallel resonant circuits have their highest impedance at the resonant frequency. This characteristic is exploited in the design of filters, oscillators and other circuits.
The current in an LC circuit is significant because it creates oscillations between the inductor and capacitor, leading to the circuit's resonant frequency. This current affects the overall behavior by determining the rate at which energy is exchanged between the inductor and capacitor, influencing the amplitude and frequency of the oscillations in the circuit.
Answer:A given combination of R,L and C in series allows the current to flow in a certain frequency range only.For this reason it is known as an acceptor circuit i.e.,it accepts some specific frequencies....
In an L-C-R AC series circuit, resonance occurs when the capacitive and inductive reactances cancel each other out, resulting in minimum impedance. This causes the current in the circuit to be at its maximum and the power factor to be unity. By measuring the frequency at which resonance occurs, one can determine the values of the inductor, capacitor, and resistor in the circuit.
THE PARALLEL rlc CIRCUIT IS CALLED A REJECTOR CIRCUIT BECAUSE IT REJECTS DOWN THE CURRENT. THE REASON IS AT RESONANCE THE IMPEDENCE OF THE CAPACITOR BECOMES EQUAL TO THAT OF THE INDUCTOR SO NO CURRENT FLOWS. AT LOW FREQUENCY THE CAPACITIVE REACTANCE IS LOW SO ALL THE CURRENT FLOWS THROUGH THE INDUCTOR AND WHEN THE FREQUENCY IS HIGH ALL THE CURRENT WILL FLOW THROUGH THE CAPACITOR BECAUSE AT THAT POINT THE REACTANCE OF THE CAPACITOR IS LOW. SO WE OBTAIN A V-SHAPED GRAPH WITH THE PEAK OF V INDICATING THE REJECTION OF CURRENT.
The bandwidth is the difference between the frequencies at which the average power dissipated is one half the maximum value or current is 1/square root(2) times its maximum value. One frequency is greater than and the other is smaller than resonant frequency and they are symmetrical about it.
That depends on the circuit. For a pure resistive circuit (no inductance and capacitance), the frequency will have no effect on the current.
With a series RLC circuit the same current goes through all three components. The reactance of the capacitor and inductor are equal and opposite at the resonant frequency, so they cancel out and the supply voltage appears across the resistor. This means that the current is at its maximum, but that current, flowing through the inductor and the capacitor, produces a voltage across each that is equal to the current times the reactance. The voltage magnification is the 'Q factor', equal to the reactance divided by the resistance.