Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be about 100 V. very small, say about 2 or 3 V. zero. 250 V. about 100 V. very small, say about 2 or 3 V. zero. 250 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 3 only 1, 3 1, 2 and 3 1, 2, 3 and 4 3 only 1, 3 1, 2 and 3 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motors normally use cast aluminium rotor because aluminium is of low resistivity. easy to cast owing to its low melting point and is easily available. lighter in weight. cheaper in cost. of low resistivity. easy to cast owing to its low melting point and is easily available. lighter in weight. cheaper in cost. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation of the synchronous generator fails, it acts as a/an synchronous generator. synchronous motor. induction motor. induction generator. synchronous generator. synchronous motor. induction motor. induction generator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM is running at a full load speed of 980 rpm. If it delivers an air gap power of 98000 Watt, calculate the rotor ohmic loss? 1920 Watt. 1800 Watt. 1960 Watt. 980 Watt. 1920 Watt. 1800 Watt. 1960 Watt. 980 Watt. ANSWER DOWNLOAD EXAMIANS APP