Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/2. PN/3000. PN/120. PN/60. PN/2. PN/3000. PN/120. PN/60. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What are the starters used for starting of cage motors? Auto transformer starter. Star-delta starter. All of these. DOL starter. Auto transformer starter. Star-delta starter. All of these. DOL starter. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine torque is proportional to which of the following? None of these both A and B flux(φ) armature current(Ia) None of these both A and B flux(φ) armature current(Ia) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to reactance voltage. high resistance of carbon brushes. armature reaction. presence of commutator. reactance voltage. high resistance of carbon brushes. armature reaction. presence of commutator. 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 commutator action is not possible otherwise it gives more uniform air-gap flux distribution dc machines are comparatively low rating machines. it reduces field structure iron losses commutator action is not possible otherwise it gives more uniform air-gap flux distribution dc machines are comparatively low rating machines. it reduces field structure iron losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Eg (generated emf) and Eb (back emf) both are changes. none of above. same. different. changes. none of above. same. different. ANSWER DOWNLOAD EXAMIANS APP