Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 1500 rpm. 4000 rpm. 3000 rpm. 3600 rpm. 1500 rpm. 4000 rpm. 3000 rpm. 3600 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the increase in the torque expressed as percentage of initial torque, if current drawn by the dc series motor is increased from 10A to 11A? 41% 10% 11% 21% 41% 10% 11% 21% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of bearing is provided in small induction motors to support the rotor shaft? Ball bearings. None of these Cast iron bearings. Bush bearings. Ball bearings. None of these Cast iron bearings. Bush bearings. 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 100% reduced to half remain unaltered increase by 200% increase by 100% reduced to half remain unaltered increase by 200% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 3/4. 9/16. 4/3. 16/9. 3/4. 9/16. 4/3. 16/9. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer which of the following losses are zero? All of these Copper loss Rotational loss Iron loss All of these Copper loss Rotational loss Iron loss ANSWER DOWNLOAD EXAMIANS APP