Armature current resistance control

Field resistance control

Ward-Leonard control

None of these

Shunt motor is suitable for electric trains

Series motor is suitable for machine tools

Series motor is suitable for belt driven machines

Compound motor is suitable for fly-wheel drive

D.C. shunt motor

D.C. series motor

Cumulative compound motor

Differential compound motor

Line voltage too high

Short-circuit in the field winding

Pitted starter contact terminals

Wrong grade of carbon brushes

Increasing the back e.m.f. with a resistor

Limiting the armature current with a shunt resistor

Changing the voltage with a starter

Changing the field current by a field rheostat