A balanced three$-$phase wye$-$connected load is connected to a balanced three$-$phase

wye$-$connected voltage.

a$)$ Sketch and with complete labels the equivalent circuit of the three$-$phase

system.

b$)$ Prove that the magnitude of the line current is $\backslash (\backslash$sqrt$\{3\}\backslash )$ times the phase current and the phase angle for the line current is lagging the phase angle of the phase current by $30$ degree.