Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve efficiency. improve starting torque. improve power factor. reduce copper loss. improve efficiency. improve starting torque. improve power factor. reduce copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following transformer insulating oil generally used in India? Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Paraffin based insulating oil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If iron loss and full load copper loss of any transformer are denoted by Pi and Pc, then the load corresponding to maximum efficiency is given by (Pi / Pc)1.6 × full Load. (Pi / Pc)2 × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc) × full Load. (Pi / Pc)1.6 × full Load. (Pi / Pc)2 × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc) × full Load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor runs at a no-load speed of 1140 rpm. At full load, armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full-load speed in rpm is 1203 1080 1000 1200 1203 1080 1000 1200 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The short circuit test on a transformer is conducted to obtain core loses only. hysteresis loss. eddy current loss. copper losses. core loses only. hysteresis loss. eddy current loss. copper losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce hysteresis loss only. reduce eddy current loss only. reduce both eddy current and hysteresis loss. increase the permeability. reduce hysteresis loss only. reduce eddy current loss only. reduce both eddy current and hysteresis loss. increase the permeability. ANSWER DOWNLOAD EXAMIANS APP