Electrical Machines In a transformer operating at constant voltage if the input frequency increases, the core loss increase. decrease. remains constant. None of these increase. decrease. remains constant. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.75 p.u 0.125 p.u 0.5 p.u 0.25 p.u 0.75 p.u 0.125 p.u 0.5 p.u 0.25 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field winding connection of DC shunt motor is changed It will run in opposite direction. It will run in same direction. motor will become slow. motor will not run. It will run in opposite direction. It will run in same direction. motor will become slow. motor will not run. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cross magnetization effects which of the following? both 2 and 3 reduces the terminal voltage commutation reduction in main field flux both 2 and 3 reduces the terminal voltage commutation reduction in main field flux 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 145 Ω. 150 Ω. 375 Ω. 225 Ω. 145 Ω. 150 Ω. 375 Ω. 225 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor both back emf as well as line current fall. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current increase. both back emf as well as line current fall. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current increase. ANSWER DOWNLOAD EXAMIANS APP