Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 4% 25% 5% 2% 4% 25% 5% 2% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected 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% reduced to half remain unaltered increase by 100% increase by 200% reduced to half remain unaltered increase by 100% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ induction motor none of them. power factor at starting is high as compared to that while running. power factor at starting is low as compared to that while running. power factor at starting in the same as that while running. none of them. power factor at starting is high as compared to that while running. power factor at starting is low as compared to that while running. power factor at starting in the same as that while running. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 4000 rpm. 3000 rpm. 3600 rpm. 1500 rpm. 4000 rpm. 3000 rpm. 3600 rpm. 1500 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 0.5 at 90°C. 3 at 90°C. 1 at 90°C. 2 at 90°C. 0.5 at 90°C. 3 at 90°C. 1 at 90°C. 2 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS