Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 50 Hz 0 Hz 100 Hz 25 Hz 50 Hz 0 Hz 100 Hz 25 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine is invariably provided with forced ventilation? Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. Fractional horse power slow speed motor. Hermetically sealed motor of refrigerator. 50 MW generator in a power plant. Fractional horse power high speed motor. Fractional horse power slow speed motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of rotor current of 50 Hz induction motor operating at 4% slip? 1 Hz 2.5Hz 2HZ 50Hz 1 Hz 2.5Hz 2HZ 50Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop synchronous motor torque. induction motor torque. induction generator torque. DC motor torque. synchronous motor torque. induction motor torque. induction generator torque. DC motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. 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 1.79 Ω 3.1 Ω 2 .1 Ω 1.8 9 Ω 1.79 Ω 3.1 Ω 2 .1 Ω 1.8 9 Ω ANSWER DOWNLOAD EXAMIANS APP