**Category:** Electromagnetism

**Subtype:** AC Circuits (Alternating Current Circuits)

**Problem Description:** This problem involves an AC circuit with a resistor and a capacitor in series. It requires finding the capacitance of the capacitor given the resistance, the frequency of the AC voltage, and the phase difference between the voltage across the circuit and the current flowing through it. Specifically, the problem asks for the value of the capacitance that results in a phase difference of \(\pi / 4\) radians.