Electrical Machines which of the following type of brush and their application is/are correct All of these electro graphite → large ratings copper graphite → low voltage high current density carbon brush → normal ratings All of these electro graphite → large ratings copper graphite → low voltage high current density carbon brush → normal ratings ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature shaft must be able to with stand All of these Any unbalanced magnetic pull on the armature core. Bending moment due to weight of the armature. Twisting stains due to transmission of torque. All of these Any unbalanced magnetic pull on the armature core. Bending moment due to weight of the armature. Twisting stains due to transmission of torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field divertor resistance for a DC series motor is of order of 50 Ω 0.1 Ω 10 Ω 100 Ω 50 Ω 0.1 Ω 10 Ω 100 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 100 Hz. 25 Hz. 50 Hz. Zero Hz. 100 Hz. 25 Hz. 50 Hz. Zero Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to improve starting torque reduce magnetising current and improve power factor increase pull out torque decrease starting torque improve starting torque reduce magnetising current and improve power factor increase pull out torque decrease starting torque ANSWER DOWNLOAD EXAMIANS APP
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