Electrical Machines Oil is provided in an oil filled transformer for lubrication. cooling. insulating. both cooling and insulation. lubrication. cooling. insulating. both cooling and insulation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 2 KVA transformer has iron loss of 150 W and full load copper loss of 250 W. The maximum efficiency of the transformer would occur when the total loss is 250 W 400W 500 W 300 W 250 W 400W 500 W 300 W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ slip ring motor has any of the above. double cage rotor. short-circuited rotor. wound rotor. any of the above. double cage rotor. short-circuited rotor. wound rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC generators has rising V-I characteristics? Shunt. Series. None of them. Compound. Shunt. Series. None of them. Compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 970 RPM 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine is invariably provided with forced ventilation? Hermetically sealed motor of refrigerator. Fractional horse power slow speed motor. Fractional horse power high speed motor. 50 MW generator in a power plant. Hermetically sealed motor of refrigerator. Fractional horse power slow speed motor. Fractional horse power high speed motor. 50 MW generator in a power plant. ANSWER DOWNLOAD EXAMIANS APP