A coil of inductance 10 H and resistance 40 ohm is connected in series with a capacitance and supplied by a source of variable frequency. If the maximum current is found at frequency 1000 rad/sec, then the Q-factor of the circuit will be ________.

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.