Electrical Machines With the increase in speed of DC motor Back emf increase but line current falls. Both back emf as well as line current fall. Back emf falls and line current increase. Both back emf as well as line current increase. Back emf increase but line current falls. Both back emf as well as line current fall. Back emf falls and line current increase. Both back emf as well as line current increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 240 rpm. 470 rpm. 450 rpm. 540 rpm. 240 rpm. 470 rpm. 450 rpm. 540 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions hunting of synchronous motor is likely to occur ? Over-excitation. Small and constant load. Over-loading for long period. Periodic variation of load. Over-excitation. Small and constant load. Over-loading for long period. Periodic variation of load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T ∝ P. T ∝ √P. T2 ∝ P3. T is independent of P. T ∝ P. T ∝ √P. T2 ∝ P3. T is independent of P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 25 %. 15 %. 50 %. 10 %. 25 %. 15 %. 50 %. 10 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If terminal voltage of one 1000 rpm shunt motor is reduced to half the speed of the motor will be 1000 rpm 500 rpm 250 rpm 2000 rpm 1000 rpm 500 rpm 250 rpm 2000 rpm ANSWER DOWNLOAD EXAMIANS APP
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