CBSE 12 Physics Part 1 | 7. ALTERNATING CURRENT by Pavan | Learn Smarter
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7. ALTERNATING CURRENT

The chapter covers alternating current (ac) and its properties, particularly focusing on ac voltages and currents as they apply to resistors, inductors, and capacitors. Key topics include the phase relationships between voltage and current, the use of phasors for circuit analysis, resonant frequency in RLC circuits, and the function of transformers in altering voltage levels. The chapter concludes with various exercises and practical applications of these concepts.

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Sections

  • 7

    Alternating Current

    Alternating current (AC) is characterized by a voltage that varies over time, commonly representing electrical energy distribution, with key properties that differentiate it from direct current (DC).

    Learning Practice

  • 7.1

    Introduction

    This section introduces alternating current (AC) and its significance compared to direct current (DC), highlighting its widespread usage in electrical systems.

    Learning Practice

  • 7.2

    Ac Voltage Applied To A Resistor

    This section discusses how alternating current (AC) voltage applied to a resistor behaves, demonstrating key concepts such as phase relationship, current amplitude, and power dissipation.

    Learning Practice

  • 7.3

    Ac Voltage Representation Of Current And Voltage By Rotating Vectors (Phasors)

    This section introduces the concept of phasors, which are used to represent ac voltages and currents, showing the phase relationships between them.

    Learning Practice

  • 7.4

    Ac Voltage Applied To An Inductor

    This section explores how an alternating current (AC) voltage affects an inductor, emphasizing the concepts of inductive reactance and the phase difference between current and voltage.

    Learning Practice

  • 7.5

    Ac Voltage Applied To A Capacitor

    This section discusses how alternating current (AC) interacts with capacitors, explaining the concepts of current and voltage in capacitive circuits.

    Learning Practice

  • 7.6

    Ac Voltage Applied To A Series Lcr Circuit

    This section discusses the behavior and analysis of an LCR circuit connected to an AC voltage source, highlighting the phase relationships and powers involved.

    Learning Practice

  • 7.6.1

    Phasor-Diagram Solution

    This section explains the use of phasors in analyzing the current and voltage relationships in AC circuits, particularly within a series RLC circuit.

    Learning Practice

  • 7.6.2

    Resonance

    Resonance in series RLC circuits occurs when the resonant frequency matches the natural frequency of the system, leading to maximum current amplitude.

    Learning Practice

  • 7.7

    Power In A Circuit: The Power Factor

    This section explores the concept of power factor in AC circuits, detailing how it influences power consumption and the relationships between voltage, current, and phase angle.

    Learning Practice

  • 7.8

    Transformers

    Transformers are devices that change alternating voltages through the principle of mutual induction.

    Learning Practice

  • 7.9

    Summary

    This section summarizes key concepts related to alternating current (AC) circuits, including voltage, current relationships, reactance, power, and transformers.

    Learning Practice

References

NCERT Study Material

Class Notes

Memorization

What we have learnt

  • Alternating currents exhibi...
  • The current through a resis...
  • Resonance in RLC circuits o...

Final Test

Revision Tests