1. The problem statement, all variables and given/known data I am having difficulty with a question on my Electrical course and the expressing a motor load voltage and current in polar form. The motor is single phase 2.8 KW efficiency 70% and 80% of full load runs with a power factor of 0.8 lagging. Voltage 400v. Express the motor loads as impedances in polar and complex number forms assuming the motors are operating at 400v. This "express" has me baffled and have spent 4 hours trying to get past this bit of the problem. My notes are not clear on the form this should take and I am now stuck as it were. 2. Relevant equations 3. The attempt at a solution I have worked out that 80% of 2.8 Kw is 2.24kw which with a voltage of 400v gives a current of 7amps. With a power factor of 0.8 I get a Cos of 36.86 degrees. The current is lagging. If current is expressed as 7xCos38.86 is voltage then 400xCos38.86? My notes are not very clear on these two expressions and can't progress until I have this information. Many thanks, Dumbkiwi.