Electrical Machines To eliminate 5th harmonic in the induced voltage phase breadth should be 72° 36° 30° 18° 72° 36° 30° 18° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a motor falls from 1100 r.p.m at no-load to 1050 r.p.m at rated load. The speed regulation of motor is 4.76%. 2.57 %. 3.76%. 2.56 %. 4.76%. 2.57 %. 3.76%. 2.56 %. 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, 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 2, 3 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, torque and supply voltage are related as T∝ V² T ∝ 1/V T ∝ V T ∝ 1/V² T∝ V² T ∝ 1/V T ∝ V T ∝ 1/V² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ratio of starting to running torque. efficiency. ratio of starting to running current. ratio of input to output voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to with stand Any unbalanced magnetic pull on the armature core. Twisting stains due to transmission of torque. Bending moment due to weight of the armature. All of these Any unbalanced magnetic pull on the armature core. Twisting stains due to transmission of torque. Bending moment due to weight of the armature. All of these ANSWER DOWNLOAD EXAMIANS APP