Electrical Machines In a synchronous motor when the rotor speed exceeds the synchronous speed during hunting the damper bars develop induction motor torque. the damper bars develop synchronous motor torque. negative sequence currents are generated. the damper bars develop induction generator torque. the damper bars develop induction motor torque. the damper bars develop synchronous motor torque. negative sequence currents are generated. the damper bars develop induction generator torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor will become lagging will become leading will remain the same None of these will become lagging will become leading will remain the same None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutation in a DC machine may be explained as a process by which electric current in a coil is reversed. how alternate flux affects the main field flux. in which magnetic field is set up. by virtue of which emf is induced in the armature conductors. by which electric current in a coil is reversed. how alternate flux affects the main field flux. in which magnetic field is set up. by virtue of which emf is induced in the armature conductors. 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, 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 1 and 4 are correct 1, 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines It is advisable to start a DC series motor with some load to Limit the current. Limit the speed. Avoid sparking. Limit the flux. Limit the current. Limit the speed. Avoid sparking. Limit the flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of conductor of a DC motor can be determined by Lenz's law. Fleming's right hand rule. Ampere law. Fleming's left hand rule. Lenz's law. Fleming's right hand rule. Ampere law. Fleming's left hand rule. ANSWER DOWNLOAD EXAMIANS APP
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