A three-phase, 50-Hz, 6-pole induction motor develops a useful torque of 120 Nm at full-load, while the rotor frequency is 2 Hz. The torque lost due to friction and windage is 10 Nm. Calculate: 1. the slip 2. the synchronous speed 3. the motor speed

B3. A three-phase, 60 Hz 4-pole induction motor has a slip of 0.05 when the output is 30 kW. The frictional loss at shaft is 300 W. Calculate the following: (i) the rotor speed in r.p.m. (ii) the torque delivered by the rotor. (iii) the torque delivered to the rotor. (iv) the rotor IR loss.