Electrical Machines Hunting in a synchronous cannot be due to windage friction. variable load. variable supply voltage. variable frequency. windage friction. variable load. variable supply voltage. variable frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. kept constant to certain value. remains unchanged. increased. decreased. kept constant to certain value. remains unchanged. increased. decreased. 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 3600 rpm. 4000 rpm. 3000 rpm. 1500 rpm. 3600 rpm. 4000 rpm. 3000 rpm. 1500 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides low noise. higher efficiency. reduced starting torque. a large starting torque. low noise. higher efficiency. reduced starting torque. a large starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at slip speed with respect to stator mmf. rotates at synchronous speed with respect to rotor. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at slip speed with respect to stator mmf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS