Electrical Machines The output power of any electrical motor is taken from the Field. Armature. Motor frame. Coupling mounted on the shaft. Field. Armature. Motor frame. Coupling mounted on the shaft. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines As compared to an induction motor, the air gap in a DC motor is less than 50%. between 50% and 90%. same. more. less than 50%. between 50% and 90%. same. more. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hopkinss test in DC motor is conducted at ? Low load. Full load. No load. None of these. Low load. Full load. No load. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 4, 6 1, 3, 5 1, 2, 5 1, 2, 6 1, 4, 6 1, 3, 5 1, 2, 5 1, 2, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to applied voltage. Back emf is equal to zero. Back emf is equal to half the applied voltage. None of above. Back emf is equal to applied voltage. Back emf is equal to zero. Back emf is equal to half the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If two 8-pole dc machines of identical armature sare wound, one with lap winding and the other with wave winding, then lap-wound machine will have more rated voltage and more current lap-wound machine will have more rated voltage and less current wave-wound machine will have more rated voltage and less current wave-wound machine will have more rated current and more voltage lap-wound machine will have more rated voltage and more current lap-wound machine will have more rated voltage and less current wave-wound machine will have more rated voltage and less current wave-wound machine will have more rated current and more voltage ANSWER DOWNLOAD EXAMIANS APP