Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 25 Hz. 50 Hz. 60 Hz. 16.67 Hz. 25 Hz. 50 Hz. 60 Hz. 16.67 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines which of the following losses are negligible in blocked rotor test? both A and B iron loss copper loss mechanical loss both A and B iron loss copper loss mechanical loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A frog leg winding is used in a DC machine to eliminate the use of compensating winding. reactance voltage produced due to communication. the use drum winding. the use equalizer in lap winding. the use of compensating winding. reactance voltage produced due to communication. the use drum winding. the use equalizer in lap winding. 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. f / s. sf. sf / 2. s2. f / s. sf. sf / 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Satisfactory commutation of DC machine requires brushes should be of proper grade and size. brushes should smoothly run in the holders. smooth, concentric commutator properly undercut. All of these brushes should be of proper grade and size. brushes should smoothly run in the holders. smooth, concentric commutator properly undercut. All of these ANSWER DOWNLOAD EXAMIANS APP