A d.c. shunt motor is rated 100hp,600 V,1800 r.p.m., and is 88% efficient when operating at rated conditions. The armature circuit resistance is 0.05Ω and the field resistance is 75Ω. Find:
i. The rated shaft torque
ii. The developed power at rated conditions
iii. The developed torque at rated conditions
iv. The external resistance required to limit the starting armature current to 150% of the rated armature current
v. The developed torque at starting.
Recall that 1hp=746 W
