Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is rectangular co- sinusoidal flat-topped sinusoidal rectangular co- sinusoidal flat-topped sinusoidal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 1Ω. 0.25Ω. 0.23Ω. 0.5Ω. 1Ω. 0.25Ω. 0.23Ω. 0.5Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited dc motor has an armature resistance of 0.5 Ω. It runs off a 250 V dc supply Drawing an armature current of 20 A at 1500 rpm. The torque developed for an armature current Of 10 A, for the same field current, will be 15.28 Nm 15.6 Nm 15.92 Nm 16.55 Nm 15.28 Nm 15.6 Nm 15.92 Nm 16.55 Nm 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 Woud be equal to 2If1. Would be equal to If1. Would be equal to If1/2. Cannot be predicted due to insufficient data. Woud be equal to 2If1. Would be equal to If1. Would be equal to If1/2. Cannot be predicted due to insufficient data. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 975 rpm 950 rpm 940 rpm 1000 rpm 975 rpm 950 rpm 940 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the a 230 V DC motor of armature resistance 0.5 Ω and back emf 200 V is 60 40 600 660 60 40 600 660 ANSWER DOWNLOAD EXAMIANS APP
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