Electrical Machines The air gap between the yoke and armature is dc machine is kept very small to avoid locking of the armature. All of these to avoid over heating. to achieve a stronger magnetic field. to avoid locking of the armature. All of these to avoid over heating. to achieve a stronger magnetic field. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 3 at 90°C. 2 at 90°C. 0.5 at 90°C. 1 at 90°C. 3 at 90°C. 2 at 90°C. 0.5 at 90°C. 1 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 4575.4 r.p.m. 1130 r.p.m. 963.8 r.p.m. 1037.5 r.p.m. 4575.4 r.p.m. 1130 r.p.m. 963.8 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The total core loss of a 400 V, 50 Hz transformer is 2400W, when it is supplied by 200 V, 25 Hz loss is 800W. Calculate eddy current loss and hysteresis loss? 800W, 1600W 1000W , 1400W 1400W, 1000W 1600W, 800W 800W, 1600W 1000W , 1400W 1400W, 1000W 1600W, 800W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Any of above. Armature voltage control. Field resistance control. Armature circuit resistance control. Any of above. Armature voltage control. Field resistance control. Armature circuit resistance control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 40W 60W 80W 100W 40W 60W 80W 100W ANSWER DOWNLOAD EXAMIANS APP
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