Electrical Machines Which of the following load normally needs starting torque more than rated torque? Air compressors. Conveyers. Centrifugal pumps. Blowers. Air compressors. Conveyers. Centrifugal pumps. Blowers. 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 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be proportional to square of rotor speed. constant independent of speed. proportional to rotor speed. zero. proportional to square of rotor speed. constant independent of speed. proportional to rotor speed. zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor power output of 3-phase induction motor is 15 KW. The rotor copper losses at a slip of 4% will be 625 W 650 W 600 W 700 W 625 W 650 W 600 W 700 W ANSWER DOWNLOAD EXAMIANS APP
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 They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and the flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will reduce by 5 %. remain unchanged. increase by 5 %. depend on other factors. reduce by 5 %. remain unchanged. increase by 5 %. depend on other factors. ANSWER DOWNLOAD EXAMIANS APP