The induced torque is zero at synchronous speed. Discussed earlier.
The curve is nearly linear between no-load and full load. In this range, the rotor resistance is much greater than the reactance, so the rotor current, torque increase linearly with the slip.
There is a maximum possible torque that can’t be exceeded. This torque is called pullout torque and is 2 to 3 times the rated full-load torque.
The starting torque of the motor is slightly higher than its full-load torque, so the motor will start carrying any load it can supply at full load.
The torque of the motor for a given slip varies as the square of the applied voltage.
If the rotor is driven faster than synchronous speed it will run as a generator, converting mechanical power to electric power.