DC Machines Quiz

What is the primary function of a DC motor?

• To regulate voltage

• To store electrical energy

• To convert mechanical energy into electrical energy

• To convert electrical energy into mechanical energy

Which type of DC motor has the armature and field winding connected in series?

• Shunt Motor

• Series Motor

• Universal Motor

• Compound Motor

What is the relationship between torque and armature current in a DC series motor?

• Torque is equal to armature current

• Torque is inversely proportional to armature current

• Torque is directly proportional to armature current

• Torque is independent of armature current

What does the term 'back emf' refer to in a DC motor?

• The voltage across the field winding

• The total voltage supplied to the motor

• The induced voltage opposing the supply voltage

• The voltage drop across the armature

Which method is used to control the speed of a DC shunt motor by varying the field flux?

• Series Parallel Method

• Shunt Field Control Method

• Field Diverter Method

• Armature Control Method

What is the main characteristic of a DC shunt motor?

• Constant speed under varying loads

• Speed varies significantly with load

• Low efficiency

• High starting torque

In a DC compound motor, what happens to the speed as the load increases?

• Speed fluctuates randomly

• Speed increases

• Speed decreases

• Speed remains constant

What is the purpose of a commutator in a DC motor?

• To increase the voltage

• To reduce friction

• To convert AC to DC

• To reverse the current direction

Which type of DC generator is used when exact control of the field current is necessary?

• Shunt Generator

• Series Generator

• Separately Excited Generator

• Self Excited Generator

What is the effect of operating a DC series motor without a load?

• It will consume less power

• It will stop functioning

• It operates normally

• It can reach dangerously high speeds