Electrical Machines Under commutation results in sparking at the middle of the brush. sparking the trailing edge of the brush. no sparking. sparking at the leading edge of the brush. sparking at the middle of the brush. sparking the trailing edge of the brush. no sparking. sparking at the leading edge of the brush. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit 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 net voltage across the armature resistance at the time of plugging will be 474 V 6 V 234 V 240 V 474 V 6 V 234 V 240 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be very small, say about 2 or 3 V. 250 V. about 100 V. zero. very small, say about 2 or 3 V. 250 V. about 100 V. zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase slip ring induction motor is wound for 4 poles on stator and 6 poles on the rotor. When 3-phase balanced voltage source at 50 Hz is applied, it will run at 1500 rpm zero speed 750rpm 1000 rpm 1500 rpm zero speed 750rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc motor with armature resistance of 0.5 ohms connected directly to a 230 Volt supply. If the armature is stationary then the current flowing through armature is 340 A. 460 A. 570 A. 250 A. 340 A. 460 A. 570 A. 250 A. ANSWER DOWNLOAD EXAMIANS APP