Get more lessons like this at http://www.MathTutorDVD.com Here we learn about the concept of 3-Phase Power in AC Circuit Analysis. We discuss the concept of separate phases in a three phase circuit, and how the phases are arranged to make the circuit balanced. We discuss why 3-phase power is useful, and how the transmission line connects the three phase source to the load in a practical circuit. We also use phasor diagrams to label each phase of the current and voltage.