The running speed of a DC series motor is basically determined by _____.

Related MCQs

• A 4 pole, 250V series motor has a wave connected armature with 1254 conductors. The flux per pole is 22mWb when the motor taking 50A. Iron and friction lossses amount to 1000W. Armature resistance 0.2Ω, series field resistance 0.2Ω. What is the speed of the motor___.
• An electrical train employing a dc series motor is running at the fixed speed, when a sudden slight drop in the mains voltage occurs. This would result in:
• A 4-pole, 3-phase induction motor is running at 4 percent slip at full load. If the speed of the motor is 720 rpm, the supply frequency is
• A 4 pole, 440V, 50Hz induction motor is running at a slip of 4%. The speed of motor is ____.
• A 4 pole, 250V series motor has a wave connected armature with 1254 conductors. The flux per pole is 22mWb when the motor taking 50A. Iron and friction lossses amount to 1000W. Armature resistance 0.2Ω, series field resistance 0.2Ω. What is the output power in H.P.
• A 200V DC series motor runs at 500rpm when taking a line current of 25A.The resistance of the armature is 0.3Ω and that of the series field is 0.5Ω. If current taken remains constant, calculate the resistance necessary to reduce the speed to 350rpm.
• A 3 phase indution motor is running with slip of 4% hving synchronous speed of 1500rpm. If rotor induced emf per phase in standstill condition is 115.47V and rotor impedance in standstill condition is 0.1+j1 Ω then torque developed ia____.
• A 220V DC series motor is taking a current of 40A. Resistance of armature is 0.5Ω and series field is 0.25Ω. What is the voltage at the brushes?
• A 220V DC series motor is taking a current of 40A. Resistance of armature is 0.5Ω and series field is 0.25Ω. What is the back emf?
• A 220V series motor takes a current of 35A and runs at 500rpm. Armature resistance of 0.25Ω and series field resistance 0.3Ω. If iron and frictional losses amount of 600W, what is the armature torque?