2. Description of Alternating Current

Concept Explanation:
Alternating Current can be described by several key parameters:

- Root Mean Square (RMS) Value: The RMS value of AC is the equivalent DC value that would deliver the same power to a resistive load. For a sinusoidal AC wave:
V_{RMS} = V₀/√2, I_{RMS} = I₀/√2

- Phase: AC signals can have a phase difference, which describes the relative position of the waveforms in time. This phase difference is important in circuits with multiple AC sources or components like capacitors and inductors.

Power in AC Circuits:
The average power delivered to a resistive load in an AC circuit is given by:
P = V_{RMS} × I_{RMS} = V₀ × I₀ / 2

Example Problem:
An AC circuit has a peak current of 5 A and a peak voltage of 220 V. Calculate the RMS values and the average power delivered to the circuit.

Solution:
The RMS values are:
I_{RMS} = I₀/√2 = 5/√2 ≈ 3.54 A
V_{RMS} = V₀/√2 = 220/√2 ≈ 155.6 V
The average power is:
P = V₀ × I₀ / 2 = 220 × 5 / 2 = 550 W