Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by sf / 2. f / s. sf. s2. sf / 2. f / s. sf. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T2 ∝ P3. T ∝ √P. T ∝ P. T is independent of P. T2 ∝ P3. T ∝ √P. T ∝ P. T is independent of P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an auto transformer, for what value of turn ratio, power transferred by inductively and conductively are same? 1 0.5 0 any of the above 1 0.5 0 any of the above ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following load normally needs starting torque more than rated torque? Blowers. Air compressors. Conveyers. Centrifugal pumps. Blowers. Air compressors. Conveyers. Centrifugal pumps. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the field system has to be provided on stator unlike synchronous machines Where in it could be on any member, because dc machines are comparatively low rating machines. it reduces field structure iron losses it gives more uniform air-gap flux distribution commutator action is not possible otherwise dc machines are comparatively low rating machines. it reduces field structure iron losses it gives more uniform air-gap flux distribution commutator action is not possible otherwise ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor drawing an armature current of Ia is operating under saturated magnetic conditions. The torque developed in the motor is proportional to Ia2 1/Ia I/Ia2 Ia Ia2 1/Ia I/Ia2 Ia ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS