How does induced current in an induction motor rotor produce torque?

In an induction motor, torque is generated through the interaction between the stator's magnetic field and the rotor's induced current. When the stator windings are powered by a three-phase supply, they create a rotating magnetic field that moves relative to the rotor conductors.1

This relative motion induces a voltage in the rotor conductors, which, because the conductors are short-circuited by end rings, causes current to flow through them. According to Lenz's law, this induced current flows in a direction that opposes the change that created it—in this case, the relative motion between the field and the rotor.123

The resulting distribution of rotor currents creates its own magnetic field that reacts with the stator's rotating field, producing a torque that acts in the same direction as the field's rotation. This torque accelerates the rotor, causing it to follow the rotating magnetic field. The rotor speed remains slightly lower than the field's synchronous speed, a difference known as slip, which is necessary to maintain the induced voltage and current required to sustain the torque.14