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Eli the ice man.
Voltage (E) before Current (I) in a coil (inductor)(L)
Current (I) before Voltage (E) in a Cap. (C)
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Wiki User
∙ 14y ago
Wiki User
∙ 12y agoAn inductor opposes current changes. In AC circuit, this opposition is observed as a lag in the current waveform.
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What happens when a inductor charges and then discharges?
AnswerWhen you connect DC voltage to an inductor, it opposes the passage of current, which generates a voltage pulse the is several times the value of the applied voltage. When you disconnect the voltage, the electromagnetic field inside the inductor collapses and all the energy it stored is released to the circuit in the form of another large pulse, but this time with opposite polarity.Remember:Inductors oppose changes in current and they store energy in an electromagnetic field.Capacitor oppose changes in voltage and they store energy in an electrostatic field.
Why current leads in capaciter?
Capacitors resist a change in voltage. It takes current to effect a voltage change, resulting in the current "leading" the voltage. Similarly, inductors resist a change in current. It takes voltage to effect a current change, resulting in the current "lagging" the voltage.
What happens when closing and breaking an inductive circuit?
When you close an inductive circuit, since an inductor resists a change in current, the initial reaction of the load is to look like a high resistance. As current builds, the resistance falls. With a theoretical source and inductor, current would eventually reach infinity, that is after infinite time, but practical sources and inductors will reach a plateau current. When you open an inductive circuit, again, since an inductor resists a change in current, the inductor attempts to maintain that current, but there is no conductivity for that current so, the inductor presents a high voltage spike in the reverse direction it was initially "charged" with. With a theoretical inductor, and theoretical infinite impedance, the voltage spike would be infinite. Again, practical inductors have a maximum voltage spike, but this spike can still be quite high, even thousands of volts, which can damage the circuit, so it is important to maintain a conduction path for the collapsing field, often a diode, or a resistor/capacitor filter.
How capacitor cancels inductive effect?
A capacitor try to leads the current while a inductor tries to legs the current so they cancels each other's effect ....
In a series RLC circuit at frequencies above resonance is the circuit capacitive or inductive?
in series you XL, voltage leads the current, and in Parallel current leads the voltage. so your answer should reflect on this theory.
What cause the voltage t lead current in an ac circuit?
Voltage leads current or, more specifically current lags voltage, in an inductive circuit. This is because an inductor resists a change in current.
Why does voltage lead current in an inductor?
From what I've read, an inductor is designed to store energy in the form of a magnetic flux. A simple inductor can be thought of as a coil of wires around a medium. The current causes the flux to go through each turn of the coil. Further examination and Faraday's law leads to this model. v= N * D(magnetic flux) Because the current inside the coil is what generates the flux, the voltage will change first, before the flowing electrons will get all the way through the inductor. The inductance constant L is the Number of turns in the wire times the ratio of the current i to the magnetic flux, which is usually a constant. L = N*flux/i Which leads to this relationship between voltage and current in an inductor: v = L* D(i) The D() function being a derivative. Because the derivative of the current will change before the current actually does, voltage leads current in an inductor.
Is there no induced voltage in an inductor unless the current is changing?
In an ideal inductor, no, there is no voltage induced across an inductor unless the current in the inductor is changing. However, since there are no ideal inductors nor power supplies, eventually an inductor will draw a constant current, i.e. the limit of the power supply; and, since no inductor has zero ohms at equilibrium, that current will translate to voltage.
Why voltage leads in Inductor?
Maximum induced voltage occurs when the current is changing at its greatest rate -this occurs when the current passes through zero. Since this voltage acts to oppose current flow, this maximum voltage acts in the negative sense when the current is acting in the positive direction. Since the supply voltage is equal, but opposite, the induced voltage, it is maximum when the current is zero -so leads by 90 degrees.
What does the voltage across a inductor do?
voltage across inductor create a flux. because of variation current developes an opposite emf.
What is the phase angle between voltage and current in a purely capacitive circuit?
Current leads voltage (or voltage lags current) by 90° in a purely capacitive circuit. Try to remember it this way: capacitors resist change in voltage, hence the voltage lags (they resist voltage change because the voltage first goes to charging up the electric field in the capacitor).Inductors resist change in current (energy in an inductor is in the form of magnetic fields, which are caused by the current through the wire). Remember an inductor is a coil (like an electromagnet, or a transformer).
What is the maximum inductor voltage when the inductor current is decreasing?
depending on the stray capacitance it can be from a few ten volts to a few kilo volts.
What happens in series lcr circuit?
in a series lcr ckt., wen d voltage across inductor Vl is > dan voltage across capacitor Vc, d voltage leads the current by an angle phi... n wen Vc > Vl d current leads the voltage by an angle phi... resonance occurs wen d reactance of inductor Xl = reactance offered by capacitor Xc... n hence at resonance, current through the circuit is max n reactence of ckt is minimum...
What is the bahaviorS of the INDUCTOR in ac supply?
Because of Ac supply, current lags voltage by 90 in Inductor.
Inductor works in direct current?
Yes, an inductor works with direct current. It is called an electromagnet. Of course, a practical electromagnet has series resistance, otherwise the current in the inductor would increase to the limit of the current/voltage source.
How current lags the voltage in inductor?
In a perfect inductor (one with no series internal resistance), the current lags the voltage by 90 degrees. If the inductor has series internal resistance, then the current will lag the voltage by less than 90 degrees - the more the resistance in series with the inductor, the smaller the angle. The tangent of the angle can be found from the ratio of the inductive reactance of the inductor to the DC resistance of the inductor. That is, Tan (phase angle) = (2 x pi x frequency (Hz) x inductance (H)) divided by resistance (ohms) eg, a 1 henry, 100 ohm inductor on 60Hz would give: (2 x pi x 60 x 1) / 100 = 3.77; tan-1(3.77) gives 75 degrees lag of current behind voltage. The cosine of this angle gives the 'power factor' for the inductor - that is, the amount of useful energy dissipated in the inductor. Cos 75 is about 0.25 - so 25% of the energy actually does useful work (heat) - the rest of the energy (75%) is returned to the supply mains when the inductor discharges its magnetic field.
Does it matter if the voltage leads the current or the current leads the voltage?
Yes. If voltage leads the current, the impedance is inductive (this would be the case if the load is a motor). If current leads the voltage, the impedance is capacitive (this would be the case for a CFL light bulb).
