A 350 V shunt motor runs at it's normal speed of 720 r/min when the armature current is 90 A. The resistance of the armature is 0.3 ohm. Determine the following: (1) The k Φ1 of the motor. If armature...

A 350 V shunt motor runs at it's normal speed of 720 r/min when the armature current is 90 A. The resistance of the armature is 0.3 ohm. Determine the following:

(1) The kΦ1 of the motor.

If armature current is 45 A and a resistance of 0.4 ohm is connected in series with the armature and the shunt field remaining constant determine the following:

(2) The new kΦ2 of the motor.

(3) The new speed of the motor in r/min

If the current is 45 A and the shunt field is reduced to 75% of it's normal value by increasing resistance in the field circuit, determine the following:

(4) The new kΦ2 of the motor.

(5) The new speed of the motor in r/min