Home Physics Alternating Current (AC)

Alternating Current (AC)

Alternating currents, peak and RMS value of alternating current/voltage; reactance and
impedance; LC oscillations (qualitative treatment only), LCR series circuit, resonance; power in
AC circuits, power factor, wattless current.
AC generator and transformer.

12th physics. NCERT notes

AC Generator

AC Generator: AC generator is the one which produces a current that alternates or changes its direction regularly after a fixed interval of time, i.e.,...
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A transformer is an electrical device used for converting low alternating voltage into a high alternating voltage and vice versa. It transfers electric power...
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Wattless Current

The current in a.c. circuit is said to be wattles if the average power consumed in the circuit is zero. The average power of an...
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Power in an AC Circuit

In an AC circuit, the current and emf vary continuously with time. Therefore power at a given instant of time is calculated and then its mean...
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Series resonance or voltage resonance in RLC circuit: The value of current at any instant in a series RLC circuit is given by At a particular...
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LCR Series Circuit

Let an alternating source of emf e be connected to a series combination of a resistor of resistance R, an inductor of inductance L...
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LC Oscillations

When a charged capacitor is allowed to discharge through a non-resistance, electrical oscillations of constant amplitude and frequency are produced. These oscillations are called...
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Representation of AC Current and Voltage by Rotating Vectors

Representation of AC Current and Voltage by Rotating Vectors The analysis of an ac circuit is by using a phasor diagram. A phasor is a...
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An ac voltage v = vm sinωt applied to a pure inductor L, drives a current in the inductor i = im sin(ωt...
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Alternating current (AC) & Alternating Voltage

Alternating current (AC) An alternating current is one whose magnitude changes sinusoidally with time. Thus alternating current is given by Where i0=current amplitude or peak value...