Electrical Machines As compared to an induction motor, the air gap in a DC motor is between 50% and 90%. less than 50%. same. more. between 50% and 90%. less than 50%. same. more. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the a 230 V DC motor of armature resistance 0.5 Ω and back emf 200 V is 660 60 40 600 660 60 40 600 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor has a rotor resistance of 0.002 Ω / phase. If the resistance is increased to 0.004 Ω / phase then the maximum torque will increase by 200% increase by 100% reduced to half remain unaltered increase by 200% increase by 100% reduced to half remain unaltered ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 10 %. 15 %. 25 %. 50 %. 10 %. 15 %. 25 %. 50 %. 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, 2, 5 1, 4, 6 1, 2, 6 1, 3, 5 1, 2, 5 1, 4, 6 1, 2, 6 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Reluctance and hysteresis motors are the types of which electrical motor? Stepper motor. 3 - Φ induction motor. DC motor. 1 - Φ synchronous motor. Stepper motor. 3 - Φ induction motor. DC motor. 1 - Φ synchronous motor. ANSWER DOWNLOAD EXAMIANS APP