Understanding Alternating Current

What is the formula for calculating the impedance in an AC circuit?

• Z = R² + X_L² + X_C²

• Z = √(R² + (X_L - X_C)²)

• Z = R / (X_L + X_C)

• Z = R + X_L + X_C

Explain the phase difference between voltage and current in an inductive circuit.

• Voltage and current are in phase with each other.

• The current leads the voltage by 90 degrees.

• In an inductive circuit, the current lags the voltage by 90 degrees.

• The current lags the voltage by 180 degrees.

How does the frequency of an AC signal affect the reactance of a capacitor?

• The frequency of an AC signal inversely affects the reactance of a capacitor; higher frequency results in lower reactance.

• Higher frequency increases reactance.

• Reactance is unaffected by frequency changes.

• Lower frequency results in higher capacitance.

What is the significance of the root mean square (RMS) value in AC circuits?

• The RMS value represents the effective value of AC voltage or current.

• The RMS value is only relevant for DC circuits.

• The RMS value is used to measure the frequency of AC signals.

• The RMS value indicates the peak value of AC voltage or current.

Describe the difference between series and parallel AC circuits in terms of voltage and current.

• In series circuits, voltage is divided equally among components; in parallel circuits, current is divided equally among components.

• In series circuits, voltage is constant and current varies; in parallel circuits, current is constant and voltage varies.

• In series circuits, both voltage and current are constant; in parallel circuits, both voltage and current vary.

• In series circuits, current is constant and voltage varies; in parallel circuits, voltage is constant and current varies.

Ac full form is