Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.573. 0.649. 0.512. 0.443. 0.573. 0.649. 0.512. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What are slot wedges in a DC machine made of? Silicon steel. Mild steel. Cast iron. Fibre. Silicon steel. Mild steel. Cast iron. Fibre. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be proportional to rotor speed. zero. proportional to square of rotor speed. constant independent of speed. proportional to rotor speed. zero. proportional to square of rotor speed. constant independent of speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will draw too much current. produce sparking at brushes. develop excessive speed and damage itself. open fuse or circuit breaker. draw too much current. produce sparking at brushes. develop excessive speed and damage itself. open fuse or circuit breaker. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 440 V, 3-phase, 10 pole and 50 HZ synchronous motor delivering a torque of 50 N-m, delivers a power of 3000W 1000W 500W 100W 3000W 1000W 500W 100W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be doubled. It will remain the same. It will be halved. It will becomes four times. It will be doubled. It will remain the same. It will be halved. It will becomes four times. ANSWER DOWNLOAD EXAMIANS APP
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