Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is co- sinusoidal sinusoidal rectangular flat-topped co- sinusoidal sinusoidal rectangular flat-topped ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating windings are used in DC generators None of these to provide path for the circulation of cooling air. to neutralize the cross magnetizing effect of the armature reaction. mainly to reduce the eddy currents by providing local short circuit. None of these to provide path for the circulation of cooling air. to neutralize the cross magnetizing effect of the armature reaction. mainly to reduce the eddy currents by providing local short circuit. ANSWER DOWNLOAD EXAMIANS APP
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 s2. sf. sf / 2. f / s. s2. sf. sf / 2. f / s. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following methods are suitable for the speed control of squirrel cage induction motor? 1. Voltage control. 2. Frequency control. 3. Pole changing method. 4. Rotor resistance control select the correct answer using the codes given below:- 2, 3 and 4. 2 and 4. 1, 2 and 3. 1, 3 and 4. 2, 3 and 4. 2 and 4. 1, 2 and 3. 1, 3 and 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A shunt generator has a critical field resistance of 300 Ω at a speed of 800 rpm if the speed is raised to 1000 rpm the critical field resistance is 225 Ω. 145 Ω. 150 Ω. 375 Ω. 225 Ω. 145 Ω. 150 Ω. 375 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Breather is provided in a transformer to absorb moisture of air during breathing. provide cold air in transformer. absorb moisture from air entering in transformer. filter the transformer oil. absorb moisture of air during breathing. provide cold air in transformer. absorb moisture from air entering in transformer. filter the transformer oil. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS