1. By what test on dc reparalely excited generator would you determine the armature reaction equivalent field current at rated armature current.
2. Assuming magnetic linearity derive the expression for speed-torque characteristic of a dc series motor using suitable symbols.
3. Compare the speed troque characteristices of a series and cummulative compound motor. Why does the compound motor have a defenite no-load speed?
4. Sketch the external characteristic of a shunt generator and explain the reason for its special nature: part of it is two-valued.