Electrical Machines High inrush of current during a starting of DC motor can efficiently be restricted to a safer value by increasing the _________________ resistance. none of above shunt field armature circuit both A and B none of above shunt field armature circuit both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature All of these They are not hard as copper brush In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 1.8 9 Ω 2 .1 Ω 3.1 Ω 1.79 Ω 1.8 9 Ω 2 .1 Ω 3.1 Ω 1.79 Ω ANSWER DOWNLOAD EXAMIANS APP
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 With the increases in field excitation of a DC generator, its generated emf increases upto a limit and then remains almost constant. increases. decreases. remains constant. increases upto a limit and then remains almost constant. increases. decreases. remains constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft of induction motor may be unbalanced due to overheating of winding. poor lubrication. uneven air gap. overload. overheating of winding. poor lubrication. uneven air gap. overload. ANSWER DOWNLOAD EXAMIANS APP