Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce eddy current loss. to reduce hysteresis loss. to reduce mechanical losses. to provide better flux linkage. to reduce eddy current loss. to reduce hysteresis loss. to reduce mechanical losses. to provide better flux linkage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at unity power factor. any of the above. lagging power factor. leading power factor. unity power factor. any of the above. lagging power factor. leading power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a motor falls from 1100 r.p.m at no-load to 1050 r.p.m at rated load. The speed regulation of motor is 3.76%. 2.57 %. 2.56 %. 4.76%. 3.76%. 2.57 %. 2.56 %. 4.76%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cross magnetization effects which of the following? reduction in main field flux reduces the terminal voltage commutation both 2 and 3 reduction in main field flux reduces the terminal voltage commutation both 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.9 Ω 31.9 Ω 15.1 Ω 31.1 Ω 15.9 Ω 31.9 Ω 15.1 Ω 31.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Resistance commutation is used generally in case of fractional kW DC machines. DC machines above 10 kW. None of these DC machines bellow 5 kW. fractional kW DC machines. DC machines above 10 kW. None of these DC machines bellow 5 kW. ANSWER DOWNLOAD EXAMIANS APP