Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be constant independent of speed. proportional to square of rotor speed. proportional to rotor speed. zero. constant independent of speed. proportional to square of rotor speed. proportional to rotor speed. zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor the torque is proportional to Power P 1/P² 1/P P² Power P 1/P² 1/P P² 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 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. C - A - B. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature reaction mmf in a DC machines has a form of trapezoidal. triangular. sinusoidal. rectangular. trapezoidal. triangular. sinusoidal. rectangular. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases keeping the terminal voltage constant, then flux will increase. any of the above. decrease. remain constant. increase. any of the above. decrease. remain constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 78.5% 67.5% 72.5% 82.5% 78.5% 67.5% 72.5% 82.5% ANSWER DOWNLOAD EXAMIANS APP