The voltage and current in a circuit are given by V(t) = Vm sin(ωt) and i(t) = Im sin(ωt + φ). If the phase angle φ between i(t) and v(t) is zero (φ = 0°), calculate the operating frequency ω in rad/sec.

In an inductive circuit, a resistance of 2 Ω is connected in series with an inductor having an inductive reactance of 4 Ω. Determine the power factor of the circuit when connected to a single-phase AC supply.

A capacitor draws a reactive power of 100 VAR due to a current of 0.87 A. Determine the capacitive reactance (XC) of the capacitor.