Electrical Machines Mechanical energy is supplied to DC generator at the rate of 4200 J / s. The generator delivers 32.2 Amp at 120 V. What is the percentage efficiency of the generator? 201.02 V. 212 V. 205 V. 210 V. 201.02 V. 212 V. 205 V. 210 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 2 .1 Ω 3.1 Ω 1.8 9 Ω 1.79 Ω 2 .1 Ω 3.1 Ω 1.8 9 Ω 1.79 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the highest possible speed of turbo alternators? 3000 rpm 1500 rpm 4000 rpm 1000 rpm 3000 rpm 1500 rpm 4000 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Demagnetization effects which of the following? commutation reduction in main field flux both B and C reduces the terminal voltage commutation reduction in main field flux both B and C reduces the terminal voltage 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 T2 ∝ P3. T ∝ √P. T ∝ P. T is independent of P. T2 ∝ P3. T ∝ √P. T ∝ P. T is independent of P. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing diverter resistance of a DC series motor causes increase in speed demanding more armature current. increase in speed but armature currnet remains the same. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed demanding more armature current. increase in speed but armature currnet remains the same. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. ANSWER DOWNLOAD EXAMIANS APP
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