Electrical Machines The armature reaction mmf in a DC machines has a form of sinusoidal. triangular. rectangular. trapezoidal. sinusoidal. triangular. rectangular. trapezoidal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In shapers and slotters which motor are preferred? Synchronous motor. Slip ring IM. Double cage motor. Squirrel cage IM. Synchronous motor. Slip ring IM. Double cage motor. Squirrel cage IM. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Would be equal to If1. Woud be equal to 2If1. Would be equal to If1/2. Cannot be predicted due to insufficient data. Would be equal to If1. Woud be equal to 2If1. Would be equal to If1/2. Cannot be predicted due to insufficient data. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the e.m.f. generated by a 4 pole lap connected DC Generator rotating at 1500 r.p.m.? Its flux per pole is 0.4 mWb and total no of armature conductors is 1000. 40 volts. 20 volts. 30 volts. 10 volts. 40 volts. 20 volts. 30 volts. 10 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to with stand 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 Any unbalanced magnetic pull on the armature core. Twisting stains due to transmission of torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Addition of 0.3 % to 4.5 % silicon to iron reduces the saturation magnetization. increases the electrical resistivity of iron. increases the hysteresis loss. None of these reduces the saturation magnetization. increases the electrical resistivity of iron. increases the hysteresis loss. None of these ANSWER DOWNLOAD EXAMIANS APP