In the field's test for dc series machines, the difficulty of obtaining readings at relatively light loads is overcome by connecting
The generator series field in series with the motor armature
A dc shunt motor is driving a constant torque load with normal excitation. If the filed current is halved then the motor will run at
A dc shunt motor is driving a mechanical load at rated voltage with normal excitation. If the load torque is increased to double of the normal one, the speed of the motor will