A coil, having both resistance and inductance, has a total effective
impedance of 50 and the phase angle of the current through it with
respect to the voltage across it is 45 lag. The coil is connected in
series with a 40 resistor across a sinusoidal supply (Fig. 10.15). The
circuit current is 3.0 A; by constructing a phasor diagram, estimate
the supply voltage and the circuit phase angle.