AC Circuits (Theory II)

These flashcards cover the key concepts related to AC circuits, including definitions of active and reactive power, circuit types, and fundamental electrical terms.

Active Power

The average power equal to the product of the rms voltage, rms current, and the cosine of the angle between them, expressed as P=VIcos ϕ.

Reactive Power

Electrical energy that alternates between the power source and the load due to reactance, measured in vars (Q=VIsin ϕ).

Apparent Power

The product of the rms voltage and rms current, represented as S=VI and measured in volt-amperes (VA).

Power Factor

The cosine of the angle (ϕ) between the current and voltage, indicating the efficiency of power usage.

Purely Capacitive Circuit

A circuit in which the current leads the voltage by 90 degrees.

Purely Inductive Circuit

A circuit in which the current lags behind the voltage by 90 degrees.

Instantaneous Power

The product of the instantaneous voltage and current at any instant in the circuit.

Phasor Diagram

A graphical representation showing the relationship between voltage and current in AC circuits.

Voltage (V)

The electric potential difference, measured in volts, representing the energy per unit charge.

Current (I)

The flow of electric charge, measured in amperes.