Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 25 W. 28 W. 36 W. 30 W. 25 W. 28 W. 36 W. 30 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If terminal voltage of one 1000 rpm shunt motor is reduced to half the speed of the motor will be 1000 rpm 250 rpm 500 rpm 2000 rpm 1000 rpm 250 rpm 500 rpm 2000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will coincide with the GNA shift forward by less than 90° shift forward by more than 90° shift forward by 90° coincide with the GNA shift forward by less than 90° shift forward by more than 90° shift forward by 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases then field flux decreases decreases. remains constant. increases. decreases decreases. remains constant. increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by increasing the input to the prime mover. cooling the armature. reducing the load voltage. increasing the excitation. increasing the input to the prime mover. cooling the armature. reducing the load voltage. increasing the excitation. ANSWER DOWNLOAD EXAMIANS APP