A single-phase circuit consists of three parallel branches, the currents in which are,
respectively, in amperes: i1 = 20 sin(314t), i2 = 30 sin(314t-/4), and i3 = 18 sin(314t+/2).
The supply voltage is u = 200 sin(314t) volts.
a) What is the frequency of the current?
b) Using the graph paper and a scale of 1 cm per 5 A, plot a phasor diagram and determine
the overall current taken from the supply (r.m.s. value) and it phase angle.
c) Determine the active and reactive currents.
d) Express the total current in the trigonometric form similar to that for the branch currents.
e) Find the impedance, resistance and reactance of the circuit.
f) Find the conductance, admittance and susceptance of the circuit.