AC Circuit: AC Current, Types and Formulas

Ans. Circuits powered by an alternating source, such as current or voltage, are known as alternating current circuits, or AC circuits. Alternating voltage or current is because the voltage or the current fluctuates around a clear mean value and periodically reverses direction. The source voltage and current in an ac circuit have a phase angle, which may be determined by dividing the resistance by the impedance.

Ans. Electrical currents that frequently change direction and experience constant value fluctuations over time are known as alternating currents (AC). An alternating voltage is a voltage whose polarity and magnitude alternate regularly. 

Ans. An electrical resistor is a passive, two-terminal device that restricts the amount of current that can flow through electrical or electronic circuits. In honour of German physicist Georg Simon Ohm, resistance is the ability to resist the flow of current and is measured in Ohms.

Ans. A two-terminal electrical device known as a capacitor is capable of storing energy in the form of an electric charge. It is made up of two electrical wires that are spaced apart by a certain amount. A vacuum may be used to fill the space between the conductors, or a dielectric, an insulating substance, may be used instead. Capacitance is the term used to describe a capacitor's capacity to hold charges. 

Ans. Resistors impose a voltage cut in an electrical circuit based on the current flow, hinder, regulate, or set the flow of current in a specific direction. Resistance is a type of impedance that is present in resistors ( R ). A resistor's resistive quantity is measured in Ohms and can take either the form of a constant value or a changing value (potentiometers). 

It is represented by: 

Is = Vs/R

Ans. The capacitor is a part that, has the capacity and ability to store energy in the form of an electrical charge. A capacitor's capacitance is expressed in Farads (F), and a DC circuit, possesses an infinite impedance (open-circuit). A capacitor, on the other hand, shorts out (has zero impedance) at very high frequencies. 

Impedance and current value can be determined using the following equations: 

Is = Vs/Xs

Ans. A wire coil that creates a magnetic field either inside the coil itself or around its core is what makes up an inductor. Henries units are used to measure an inductor's inductance quantity (H). An inductor is a short-circuit and has zero impedance in DC circuits. In contrast, an inductor has an infinite impedance at high frequencies (open-circuit). 

Impedance and current value can be determined using the following equations: 

XL =2πfL

Ans. The difference between AC and DC current are:

Ans. The definition of the parameters is as follows:

• Amplitude: Amplitude is defined as the peak value or maximum value. It is the highest positive or negative value that an alternating current can reach in a single cycle. Em or Vm and Im, which stand for the maximum values of voltage and current, respectively.
• Alternation: Alternation is defined as a one-half cycle. An electrical alternation span is 180 degrees.
• Cycle: A collection of positive and negative values is said to have completed a cycle when they are alternated or when they rotate electrically 360 degrees.
• Instantaneous value: An instantaneous value in the voltage or current value at any given moment in time. It's indicated by (i or e).
• Frequency: Frequency is the number of cycles per second that an alternating quantity produces. It is expressed by and measured in cycles per second (c/s) or hertz (Hz) (f).
• Time Frame: Time Period is the number of seconds it takes a voltage or current to complete one cycle. It's indicated by (T).
• Wave Form: A waveform is a shape created by charting the time (t) or angle (=wt) along the x-axis and the instantaneous values of an alternating quantity, such as voltage and current, along the y-axis.

Ans. There are three types of AC circuits. They are as follows: 

1. Circuit with a resistor and an inductor: The RC circuit is made up of an AC generator, a resistor, and a capacitor. A capacitor's basic components are a group of conducting plates spaced apart by an insulator. As a result, the capacitor is unable to receive a steady current. A time-varying current can add to or subtract electrical charges from the capacitor plates.
2. Circuit with a resistor, inductor, and capacitor (RLC): An RLC AC circuit has a resistor R, an inductor L, and a capacitor C connected either in series or parallel. The phase relation between these elements can be stated as the immediate current and the immediate voltage across the resistor are in phase. The instantaneous voltage over the inductor causes the immediate current to be accelerated by 90 degrees and across the capacitor, the instantaneous current is greater than the instantaneous voltage.
3. AC Resistive Circuit: The RL circuit consists of an AC generator, a resistor, and an inductor. When a circuit switch is flipped on, an RL AC circuit generates a back EMF in the inductor coil. The current takes some time to reach its maximum value. The time constant is known as the inductive time constant.