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# AC Circuit Containing Inductance Only

The AC circuit containing inductance only can store electric current in the form of magnetic energy. Learn more about its importance.

There are two forms of current which include alternating and direct current. In direct current (DC), the flow of electricity is only in one direction. In contrast, in the case of alternative current (AC), the flow of charge changes direction periodically. Hence, there is a reversal in both the voltage level and the current flow.

An AC circuit containing inductance only is a circuit that consists of only the inductor as a component. We use such inductors in the AC circuit as filters. They are known to store energy in the form of magnetic energy and hence are known for reducing fluctuation during the flow of electric current.

The AC circuit containing inductance only means that the AC circuit consists only of inductors with no influence from resistor or capacitor.

## Impact and Use of Inductor in the AC Circuit

In the case of alternating current, as the electric current flows, it sets up a magnetic effect. This magnetism alters the electromotive force. The primary role of the inductor is to reduce the fluctuation during the flow of high currents and voltage.

In the AC Circuit containing inductance only, as the applied voltage varies and reverses polarity, the inductor stores energy continuously only as magnetic energy without preventing the flow of the electric current.

Inductance also prevents voltage fluctuation. The alternating current’s opposition caused by inductance is called reactance. In the AC Circuit containing inductance only, there will be no effect of resistance and capacitance in the circuit. Hence, it will lag the voltage by an angle of 90°.

## AC Circuit Containing Inductance Only Meaning and Equation

With the AC circuit containing inductance only, as only the inductor is present, it reserves the electrical energy and converts it into a magnetic field with the current flow through it. As the direction of current or voltage changes, the impact of the time-varying magnetic field leads to the electromotive force opposing the current flow.

Hence, it is known to control the current flow’s fluctuation, and opposition is called inductive reactance.

The equation of the AC circuit containing inductance only meaning proves that the current in the pure inductive AC circuits lags the voltage by 90°.

Let the voltage in the circuit be

v = VmSin ωt

The electromotive force (EMF) in the inductor is

E = – L x dl/dt

In comparison, the EMF induced in the circuit is equal and opposite to the voltage applied.

Hence, we can imply that v = E

v = – L x dl/dt

Putting the value of v

VmSin ωt = – L x dl/dt

On integrating the sides, we can conclude that in the case of the pure inductive AC circuits, it lags the voltage by 90°.

## Understanding Inductive Reactance

Inductive reactance in the AC circuit containing inductance only is when the inductance opposes the alternating current. We measure this inductive reactance in ohms.

Let us consider how XL represents it. The voltage induced in the circuit is the counter electromotive force known to oppose change. When the flow of current is maximum, it induces the counter EMF.

In the AC circuit, which consists of only an inductor, the current is lagging compared to the voltage. The current will flow bound by the circuit’s reactance in the AC circuit containing inductance only.

It successfully stores the energy into a magnetic field as the circuit flows. It thus helps in its return if there is a collapse. This process is known as reactive power.

## AC Circuit Containing Inductance Only Importance

Let us learn about the importance of such AC circuits.

• The importance of the AC circuit containing inductance only is its ability to convert and store the electric energy into magnetic energy. Hence, the generation of EMF opposes the change of the current and controls fluctuation.
• The inductors present in the AC Circuit work and function by dropping a voltage directly proportional to the current rate of change.
• We can observe the AC Circuit containing inductance is of only importance in various devices like voltage stabilisers used in many appliances. The pure inductive AC circuit helps with stabilising fluctuation as the current is lagging the voltage by 90°.
• The instantaneous power in an AC circuit containing inductance only may be positive or negative. This power is a product of voltage and current. Therefore, it equals zero whenever the circuit’s instantaneous current or voltage is zero.

## Conclusion

The alternating current circuit has applications in a range of appliances used in our daily life.

Alternating current involves the flow of current in a way that it changes direction periodically. As the current changes direction, it periodically reverses the voltage in the AC circuits. Hence, in the AC Circuit containing inductance only, the current lags the voltage by 90°.

When the AC circuit consists of only the inductor, it helps store the electric current in the form of the magnetic field. This aspect leads to altering the electromotive force and is known to control the voltage fluctuation.

Hence, understanding the AC Circuit containing inductance only means analysing the AC circuit consisting only of the inductance without the capacitance and resistance.

Get answers to the most common queries related to the IIT JEE Examination Preparation.

## What is the use of the inductor in the AC circuit?

Ans. The inductor is a crucial component in the AC circuit. Its main role is storing electricity in the form...Read full

## Does voltage or current lag in the AC circuit containing inductance only?

Ans. The electric current lags the voltage by 90 degrees in the pure AC circuit inductor. Hence, the generat...Read full

## What is the use of an alternating current circuit?

Ans. One of the biggest advantages of alternating current over direct current is that it can transmit power ...Read full

## What is inductive reactance?

Ans. This phenomenon occurs in the pure inductance AC circuit when it opposes the flow of electric...Read full