Design of Armature core

What is the function of armature in a DC machine?

• a) To convert mechanical energy into electrical energy

• b) To convert electrical energy into mechanical energy

• c) To store electrical energy

• d) None of the above

Which material is commonly used to make the armature core in a DC machine?

• a) Copper

• b) Iron

• c) Steel

• d) Aluminum

What is the purpose of the commutator in a DC machine armature?

• a) To change the direction of current flow in the armature

• b) To change the voltage level in the armature

• c) To control the speed of the machine

• d) None of the above

Which type of winding is commonly used in DC machine armatures?

• a) Lap winding

• b) Wave winding

• c) Both a and b

• d) None of the above

What is the purpose of the insulation in the armature winding of a DC machine?

• a) To prevent short circuits between adjacent coils

• b) To reduce the losses in the armature winding

• c) To increase the output voltage of the machine

• d) None of the above

What is the function of the brushes in a DC machine?

• a) To provide power to the armature

• b) To remove the electrical energy from the armature

• c) To regulate the speed of the machine

• d) None of the above

Which type of brush is commonly used in DC machines?

• a) Carbon brush

• b) Metal brush

• c) Graphite brush

• d) Plastic brush

Which type of bearing is commonly used to support the armature in a DC machine?

• a) Ball bearing

• b) Roller bearing

• c) Sleeve bearing

• d) Magnetic bearing

Which factor does not affect the design of the armature in a DC machine?

• a) Rated voltage

• b) Rated current

• c) Rated power

• d) Rated frequency

Which type of winding is suitable for low voltage and high current applications in DC machines?

• a) Lap winding

• b) Wave winding

• c) Both a and b

• d) None of the above