Engine 2014: Electricity

1. A reversing the direct current direction through the motor series field and the motor armature
2. B reversing the direct current direction through the motor series field and maintaining the same direct current direction through the motor armature.
3. C reversing the direct current direction through the motor armature and maintaining the same direct current direction through the motor series field
4. D reversing the direct current direction through the motor armature and maintaining the same direct current direction through the motor shunt field.

Tip: press A-D to answer