I've only a few questions left on a HNC assignment and am stupmed for one reason. A voltage given by the expression v = 100sin314t + 50sin942t - 40sin1570t is applied to an impedance of (40 + j30)Ω What's required i) An expression for the instantaneous current flowing in the circuit iii) The effective rms current iv) The power supplied to the load Whats thrown me is the 40+j30.. if it was just 40Ω i could do it no problem.. Also 'i) An expression for the instantaneous current flowing in the circuit' Umm..? What? Aha.. Help would be greatly appreciated. Thanks, Jon.