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 = 1. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The flux is maximum in the following part of a DC motor: under leading pole tip. under trailing pole tip. pole core. under the interpole. under leading pole tip. under trailing pole tip. pole core. under the interpole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by sf. s2. f / s. sf / 2. sf. s2. f / s. sf / 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic circuit of a dc shunt generator with negligible armature resistance and brush contact voltage drop remains unsaturated when it delivers full-load current at rated terminal voltage. The brushes are kept in the interpolar axis and speed is maintained constant. When the load is switched off, the terminal voltage would remain the same increase decrease become zero remain the same increase decrease become zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC machine having P no of pole pairs, Z no of conductors having length L of resistivity ρ and cross section S are arranged. what is the armature resistance for simple wave-winding ? PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4Sp² PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4Sp² 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