Electrical Machines If residual magnetism of a shunt generator is destroyed accidentally it may be restored by connecting its shunt field to a DC source. to earth. in reverse. to an AC source. to a DC source. to earth. in reverse. to an AC source. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dc motor with armature winding resistance of 0.6 ohm receives a supply of 230 Volt. If the back emf produced during running condition is equal to 210 volt. Calculate the current flowing through the armature at this point. 43 Amp. 33.33 Amp. 44.47 Amp. 29 Amp. 43 Amp. 33.33 Amp. 44.47 Amp. 29 Amp. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to reactance voltage. armature reaction. high resistance of carbon brushes. presence of commutator. reactance voltage. armature reaction. high resistance of carbon brushes. presence of commutator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 1500 rpm. 3000 rpm. 3600 rpm. 4000 rpm. 1500 rpm. 3000 rpm. 3600 rpm. 4000 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 1-phase induction motor, if the forward torque slip is S, what is the backward torque slip? 1-S S 2-S 1/S 1-S S 2-S 1/S ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A part an alternator winding consist of eight coils in series, each having an emf of 20 V rms induced in it. Coils are placed in successive slots and between each slot and the next, there is an electrical phase displacement of 30°. Find the emf of eight coils in series 56.91 V. 86.91 V. 76.91 V. 66.91 V. 56.91 V. 86.91 V. 76.91 V. 66.91 V. ANSWER DOWNLOAD EXAMIANS APP