Electrical Machines The armature resistance of the dc motor is generally of the range 0.1 ohm. 0.5 ohm. 100 ohm. 50 ohm. 0.1 ohm. 0.5 ohm. 100 ohm. 50 ohm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ f/φ E ∝ φf E ∝ 1/(φf) E ∝ φ/f E ∝ f/φ E ∝ φf E ∝ 1/(φf) E ∝ φ/f ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% increase 36.36% decrease 18.18% increase 36.36% increase 36.36% increase 36.36% decrease 18.18% increase 36.36% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At slip s = 1 torque developed in machine is none. starting torque. electromagnetic torque. maximum torque. none. starting torque. electromagnetic torque. maximum torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Mechanical energy is supplied to DC generator at the rate of 4200 J / s. The generator delivers 32.2 Amp at 120 V. What is the percentage efficiency of the generator? 210 V. 205 V. 212 V. 201.02 V. 210 V. 205 V. 212 V. 201.02 V. ANSWER DOWNLOAD EXAMIANS APP