AC Source & Phasor

An AC source produces a sinusoidal voltage v(t) = V₀ sin(ωt), where V₀ is the peak amplitude and ω = 2πf is the angular frequency.

Indian mains: 230 V rms, 50 Hz. So V₀ ≈ 325 V and T = 20 ms.

RMS value is the DC-equivalent — the steady DC voltage that would deliver the SAME average power to a resistor.

For a sine wave: V_rms = V₀/√2 ≈ 0.707 V₀.

Phasor representation: V₀ is the length of a vector rotating at ω; its y-projection (or x-projection, by convention) gives the instantaneous value.

The PHASE of an AC source is its angular offset at t = 0 — it sets when the wave 'starts'.

AC waveforms can also be triangular or square, but unless otherwise stated 'AC' means sinusoidal.