leakage reactance, and slip (, or , , and ). Magnetizing reactance (). Paraphrasing from Alger in Knowlton, an induction motor is simply an electrical transformer the magnetic circuit of which is separated by an air gap between the stator winding and the moving rotor winding. The equivalent circuit can accordingly be shown either with equivalent circuit components of respective windings separated by an ideal transformer or with rotor components referred to the stator side as shown in the following circuit and associated equation and parameter definition tables. The following rule-of-thumb approximations apply to the circuit: Maximum current happens under locked rotor current (LRC) conditions and is somewhat less than , with LRC typically ranging between 6 and 7 times rated current for standard Design B motors. Breakdown torque happens when and such that and thus, with constant voltage input, a low-slip induction motor's percent-rated maximum torque is about half its percent-rated LRC. The relative stator to rotor leakage reactance of standard Design B cage induction motors is . Neglecting stator resistance, an induction motor's torque curve reduces to the Kloss equation , where is slip at . Linear induction motor Linear induction motors, which work on the same general principles as rotary induction motors (frequently three-phase), are designed to produce straight line motion. Uses include magnetic levitation, linear propulsion, linear actuators, and liquid metal pumping. See also AC motor Circle diagram Induction generator Premium efficiency Variable refrigerant flow Notes References Classical sources External links Who Invented the Polyphase Electric Motor? Silvanus Phillips Thompson: Polyphase electric currents and alternate current motors Induction motor topics from Hyperphysics website hosted by C.R. Nave, GSU Physics and Astronomy Dept. Cowern Papers Electric motors AC motors Inventions by Nikola Tesla 19th-century inventions