Problem 6: A series connected DC motor needs to provide an output torque of 15 Nm with negligible rotational losses. The motor has resistance values of Ra=32 and RF=222 while the magnetization curve for the motor is shown below. The motor is connected to a motor controller that can provide a VI from 50 V to 350 V. a) What is the smallest value of VI for which the motor will still be able to turn for the desired torque? (10 points) b) What is the most efficient VT and the motor speed corresponding to this VT? (10 points) EA Es=150%), =125 red /s