The phase angle in an RC circuit is always positive.

Explanation:

An RC circuit is a combination of a resistor (R) and a capacitor (C) connected in series or parallel. When an alternating current (AC) is applied to the circuit, the voltage across the resistor and capacitor will have a phase difference, known as the phase angle.

The phase angle represents the time delay between the voltage across the resistor and the voltage across the capacitor. It is measured in degrees or radians and determines the relationship between the current and voltage waveforms in the circuit.

Phase Angle Calculation:

The phase angle (ϕ) in an RC circuit can be calculated using the formula:

ϕ = arctan(1 / ωRC)

Where:
- ω is the angular frequency of the AC signal
- R is the resistance in the circuit
- C is the capacitance in the circuit

Positive Phase Angle:

In an RC circuit, the phase angle is always positive. This means that the voltage across the capacitor lags behind the voltage across the resistor.

The reason for the positive phase angle is the reactive nature of the capacitor. The capacitor stores energy in an electric field and releases it over time. As a result, the voltage across the capacitor takes some time to reach its maximum value, causing a time delay or phase shift in the waveform.

Physical Interpretation:

The positive phase angle indicates that the voltage across the capacitor is lagging behind the voltage across the resistor. This can be physically interpreted as follows:

- At the start of the AC cycle, the voltage across the resistor reaches its maximum value, while the voltage across the capacitor is still building up.
- As time progresses, the voltage across the capacitor increases, but it never reaches the same peak value as the voltage across the resistor.
- The time delay or phase shift between the resistor and capacitor voltages is always positive, indicating that the capacitor voltage lags behind.

Conclusion:

In conclusion, the phase angle in an RC circuit is always positive. This positive phase angle represents the time delay or phase shift between the voltage across the resistor and the voltage across the capacitor.