DC Motors Differentially compound D.C. motors can find applications requiring Frequent on-off cycles Variable speed Low starting torque High starting torque Frequent on-off cycles Variable speed Low starting torque High starting torque ANSWER DOWNLOAD EXAMIANS APP
DC Motors Where D.C. motor of H.P. 12 or more requires frequent starting, stopping, reversing and speed control Three point starter is used All above can be used Drum type controller is used Four point starter is used Three point starter is used All above can be used Drum type controller is used Four point starter is used ANSWER DOWNLOAD EXAMIANS APP
DC Motors The back emf in a dc motor ______ Opposes the applied voltage None of the listed here Aids the applied voltage Aids the armature current Opposes the applied voltage None of the listed here Aids the applied voltage Aids the armature current ANSWER DOWNLOAD EXAMIANS APP
DC Motors When the armature of a D.C. motor rotates, e.m.f. induced is Back e.m.f. None of these Mutually induced e.m.f. Self-induced e.m.f. Back e.m.f. None of these Mutually induced e.m.f. Self-induced e.m.f. ANSWER DOWNLOAD EXAMIANS APP
DC Motors The main disadvantage of the Ward-Leonard control method is High maintenance cost Low efficiency at high loads High initial cost All of these High maintenance cost Low efficiency at high loads High initial cost All of these ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a dc motor is comnected across the AC supply it will Not run Run at lower speed Burn due to heat produced in the field winding by eddy currents Run at normal speed Not run Run at lower speed Burn due to heat produced in the field winding by eddy currents Run at normal speed ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS