Electrical Machines The armature reaction mmf in a DC machines has a form of rectangular. triangular. sinusoidal. trapezoidal. rectangular. triangular. sinusoidal. trapezoidal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2 A armature current at no-load, when the armature current is changed to 20 A 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. none of above. 1037.5 r.p.m. 4575.4 r.p.m. 1130 r.p.m. none of above. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a 3 - Φ induction motor is clockwise when it is supplied with 3 - Φ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be C - A - B. B - C - A or C - A - B. B - C - A. A - C - B. C - A - B. B - C - A or C - A - B. B - C - A. A - C - B. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor especially the cage rotors slots are nearly parallel to shaft axis. This is called skewing. crawling. cogging. slip. skewing. crawling. cogging. slip. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited DC generator, running at rated speed, has 6 volts across its armature terminals with no field current. When field winding is excited with one ampere, the voltage builds up to 250 V at no load. In case field current is reduced to zero, with the speed remaining unaltered, the armature terminal voltage would be zero more than 6 V less than 6 V 6 V zero more than 6 V less than 6 V 6 V ANSWER DOWNLOAD EXAMIANS APP
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