Alternating Current

Alternating Current

Edited By Team Careers360 | Updated on May 06, 2022 10:36 AM IST

Introduction:
A constant shift in the amount of alternating current occurs throughout time, and its direction is reversed on a regular basis. The perfect resistive AC circuit has just R ohms of pure resistance. Inductance and capacitance will have no effect on this circuit. Backwards and forwards, the alternative current and voltage flow in both directions. As a result, current and voltage have a sine waveform. The power is wasted by the resistors in a completely resistive circuit, and the phase of both voltage and current remains the same. This indicates that both the voltage and the current have reached their maximum levels at the same moment. The mean value of alternating current across a whole cycle is commonly defined as the average of the instantaneous values. Asymmetrical waves, such as a sinusoidal voltage or current waveform, have a positive half cycle that equals the negative half cycle. This means that after completing a full cycle, the mean result is equal to zero. The mean value is derived by eliminating the signs since both cycles do some work. As a result, only the positive cycle may be used to calculate the average value of alternating amounts of sinusoidal waves.

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List of topics according to NCERT and JEE Main/NEET syllabus:

About alternating current
Alternating Current Production
Application of Alternating Current
Alternating Current Waveform
Average Value of AC
RMS Value of AC
Phasor Diagrams
AC Circuit Containing Resistance
AC Circuit Containing Inductance
capacitor in alternating current
Alternating Current VS Direct Current
L.C.R circuits
Induced EMF
Power Factor
AC Circuits
Transformer

Related Topics,

Important concepts and Laws:

Containing an AC Circuit with solely inductance is known as an inductance circuit. In this circuit, resistance and capacitance will have no effect. The current will be 90 degrees behind the voltage in this case. When current travels through the inductor, it stores electrical energy in the magnetic field. The time-varying magnetic field creates emf, which opposes the flow of current, as the current varies. Inductive reactance is the term for this resistance to current flow. A capacitor in an alternating current circuit is a circuit that simply contains a pure capacitor. It has no effect on resistance or inductance qualities. In the electric field, the capacitor will store electric power. Capacitance is the term for this. When a voltage is placed across the capacitor's plates, an electric field is created across the plates. There will be no current flows between them as well. A transformer is a device that converts voltage between two different values. The output end's power is equal to the input end's power. The only thing that will change is the voltage. An alternating current generator/dynamo is a mechanism that converts mechanical energy into alternating current energy. It is one of the most often used uses of the electromagnetic induction phenomena. Nikola Tesla, a Yugoslav physicist, was the inventor of the generator. The term "generator" is misleading because the machine does not create anything. It is, in reality, an alternator that converts one type of energy into another. An a.c generator works on the principle of electromagnetic induction, which states that an e.m.f. is induced in a coil anytime the quantity of magnetic flux coupled to it varies. It lasts as long as the magnetic flux across the coil continues to vary.

NCERT Notes Subject wise link:

Importance of alternating current for class 12

Physics contains the greatest chapters that will provide pupils with a solid foundation. The chapter on the alternating current will help students understand the fundamentals of electricity a bit better. Class 12 Chapter 7 Physics aid’s pupils in comprehending all definitions and topics related to alternating current. Alternating Current is a simple and high-scoring chapter in both the JEE Mains and JEE Advanced exams. This chapter focuses only on the behaviour of various types of AC circuits, including resistor, capacitor, and inductor circuits. It also discusses phasors, which is an important topic.

NCERT Solutions Subject wise link:

NCERT Exemplar Solutions Subject wise link:

Frequently Asked Questions (FAQs)

1. Define ac current?

An alternating current is a current whose amplitude fluctuates over time and whose direction is reversed on a regular basis.

2. Who created the alternating current?

Nikola Tesla, a Yugoslav physicist, created the alternating current

3. What is the meaning of dc current?

Direct current (DC) is the one-directional flow of electric charge

4. Give some ac and dc current examples?

Examples of DC electronics include Cell phones, Flat-screen TVs (AC goes into the TV, which is converted to DC) , Flashlights, Hybrid and electric vehicles. Many equipment, particularly domestic appliances like lights, washing machines, and refrigerators, rely on AC power, which is provided straight from the power grid through power plugs.

5. Is ac better than dc?

Because of the easy ways we may use to scale up and down voltages, AC is superior to DC when transporting power over long distances. Transformers can accomplish this with AC but not with DC, or at least not in a way that is as sophisticated as DC.

6. What is the difference between Alternating Current and Direct Current

The terms AC and DC are used to describe different kinds of current flow in a circuit. The electric charge (current) in direct current (DC) only flows in one direction. In alternating current (AC), on the other hand, the direction of electric charge changes on a regular basis.