Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Motors for fans and pumps are selected in the rpm range 500 to 720. 375 to 500. 720 to 920. 1440 to 2880. 500 to 720. 375 to 500. 720 to 920. 1440 to 2880. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A shunt generator has a critical field resistance of 300 Ω at a speed of 800 rpm if the speed is raised to 1000 rpm the critical field resistance is 375 Ω. 150 Ω. 225 Ω. 145 Ω. 375 Ω. 150 Ω. 225 Ω. 145 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging of induction motor occurs at low voltage and when stator and rotor poles are not equal. low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are not equal. low voltage and when stator and rotor poles are not equal. low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are not equal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor wound rotor motor is mainly is used in application where low starting torque. high starting torque. power factor is less. less costly motor is not required. low starting torque. high starting torque. power factor is less. less costly motor is not required. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.78 Ω. 0.66 Ω. 0.24 Ω. 0.45 Ω. 0.78 Ω. 0.66 Ω. 0.24 Ω. 0.45 Ω. ANSWER DOWNLOAD EXAMIANS APP
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