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 / 2. f / s. sf. s2. sf / 2. f / s. sf. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The torque angle, in a synchronous motor, is the angle between None of these the rotating stator flux and rotor flux. magnetizing electric current and back emf. the supply voltage and the back emf. None of these the rotating stator flux and rotor flux. magnetizing electric current and back emf. the supply voltage and the back emf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If residual magnetism of a shunt generator is destroyed accidentally it may be restored by connecting its shunt field to a DC source. in reverse. to earth. to an AC source. to a DC source. in reverse. to earth. to an AC source. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC series motor is best suited for electric traction as It is cheaper in cost. It develops high starting torque. It runs at very high speed at light load. It consume less power. It is cheaper in cost. It develops high starting torque. It runs at very high speed at light load. It consume less power. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A compound dc generator is delivering full load current at a terminal voltage of 230 V. Its series-field winding gets short circuited. If its terminal voltage 1. becomes more than 230 V, it is overcompounded generator 2. becomes more than 230 V, it is differentially compounded generator 3. becomes less than 230 V, it is overcompounded generator 4. becomes less than 230 V, it is differentially compounded generator 5. becomes less than 230 V, it is level compounded generator From these, the correct answer is 2, 3, 5 2,3 1, 4 1, 4, 5 2, 3, 5 2,3 1, 4 1, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous motor electromagnetic power varies directly as square of applied voltage directly as applied voltage inversely as applied voltage None of these directly as square of applied voltage directly as applied voltage inversely as applied voltage None of these ANSWER DOWNLOAD EXAMIANS APP