Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 50 Hz. 25 Hz. 60 Hz. 16.67 Hz. 50 Hz. 25 Hz. 60 Hz. 16.67 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to high resistance of carbon brushes. armature reaction. presence of commutator. reactance voltage. high resistance of carbon brushes. armature reaction. presence of commutator. reactance voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW? generator 2 gets over load None of these 200 MW and 400MW generator 1 gets over load generator 2 gets over load None of these 200 MW and 400MW generator 1 gets over load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor torque or load angle δ ------------- with increase in load remains unaffected increases None of these decreases remains unaffected increases None of these decreases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing divertor resistance of a DC series motor Increase in speed demanding more armature current. Decrease in speed demanding less armature current. Increase in speed but armature currnet remains the same. Decrease in speed but armature current remains the same. Increase in speed demanding more armature current. Decrease in speed demanding less armature current. Increase in speed but armature currnet remains the same. Decrease in speed but armature current remains the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the speed of stator rotating magnetic field with respect to rotor rotating magnetic field? None of these Slip speed Synchronous speed Zero None of these Slip speed Synchronous speed Zero ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS