Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What type of connection is made in between the inter-pole and the field winding? None of the options. Parallel. Compound. Series. None of the options. Parallel. Compound. Series. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 phase stepper motor has 6 stator poles and 4 rotor poles, then find the step angle? 30° 60° 10° 45° 30° 60° 10° 45° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine shape of armature MMF wave is? Triangular and directed towards main pole. Triangular and directed towards brush axis. Saddle shape. Peaky in nature. Triangular and directed towards main pole. Triangular and directed towards brush axis. Saddle shape. Peaky in nature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve starting torque. reduce copper loss. improve efficiency. improve power factor. improve starting torque. reduce copper loss. improve efficiency. improve power factor. 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 = 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 Xd = 10.8Ω and Xq = 8Ω Xd = 8Ω and Xq = 10.8Ω ANSWER DOWNLOAD EXAMIANS APP