The resistance measured between each pair of slip rings of a three-phase, 60-Hz, 250-kW, 16 poles, and wound-rotor induction motor is 49 mΩ. With the slip tings short-circuited, the full-load slip is 0.041. For the purposes of this problem, it may be assumed that the slip-torque curve is a straight line from no load to full load. The motor drives a fan which requires 250 kW at the full-load speed of the motor. Assuming the torque to drive the fan varies as the square of the fan speed, what resistance should be connected in series with the rotor resistance to reduce the fan speed to 400r/min?