Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 6 ohms. 2.2 ohms. 5.7 ohms. 1.9 ohms. 6 ohms. 2.2 ohms. 5.7 ohms. 1.9 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 95% 94% 92% 96% 95% 94% 92% 96% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V DC machine has an armature resistance 1Ω. If the full load current is 20 A, the difference of induced voltage and generator is 40 V. 0 V. 60 V. 20 V. 40 V. 0 V. 60 V. 20 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 6 pole DC machine, 90 mechanical degrees correspond to which of the following electrical degree? 180. 45. 270. 30. 180. 45. 270. 30. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Increase. Reduce. Oscillate around the normal speed. Remain unaltered. Increase. Reduce. Oscillate around the normal speed. Remain unaltered. 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 remain unaltered reduced to half increase by 200% increase by 100% remain unaltered reduced to half increase by 200% increase by 100% ANSWER DOWNLOAD EXAMIANS APP