Electrical Machines In travelling cranes for crane travel, trolley and boom hoist which motor is preferred? Stepper motor. DC differential compound motor. Slip ring induction motor. Synchronous motor. Stepper motor. DC differential compound motor. Slip ring induction motor. Synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature resistance of a permanent magnet dc motor is 0.8 Ohm. At no load, the motor draws 1.5 A from a supply voltage of 25 V and runs at 1500 rpm. The efficiency of the motor while it is operating on load at 1500 rpm drawing a current of 3.5 A from the same source will be 59.2%. 48.0%. 57.1%. 88.8%. 59.2%. 48.0%. 57.1%. 88.8%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The polarity of a DC generator can be reversed by reversing field electric current as well as direction of rotation. increasing field current. any of above. reversing the field current. reversing field electric current as well as direction of rotation. increasing field current. any of above. reversing the field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Series booster is a shunt wound DC generator. series wound DC generator. permanent magnet DC generator. separately excited DC generator. shunt wound DC generator. series wound DC generator. permanent magnet DC generator. separately excited DC generator. 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. 145 Ω. 150 Ω. 225 Ω. 375 Ω. 145 Ω. 150 Ω. 225 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor has a rotor resistance of 0.002 Ω / phase. If the resistance is increased to 0.004 Ω / phase then the maximum torque will increase by 100% reduced to half remain unaltered increase by 200% increase by 100% reduced to half remain unaltered increase by 200% ANSWER DOWNLOAD EXAMIANS APP