Electrical Machines If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then Ph will increase but Pe will decrease Pe will increase but Ph will decrease Ph will decrease but Pe will remain same both hysteresis loss(Ph) and eddy current loss(Pe) will increase Ph will increase but Pe will decrease Pe will increase but Ph will decrease Ph will decrease but Pe will remain same both hysteresis loss(Ph) and eddy current loss(Pe) will increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type motors are preferred for lathes? Synchronous motor. DC shunt motors. Either A or B. Squirrel Cage induction motor. Synchronous motor. DC shunt motors. Either A or B. Squirrel Cage induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To increase the flux cutting by the rotor. To convert alternating supply current to direct current. None of these. To absorb the mechanical shocks produced during running condition. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. None of these. To absorb the mechanical shocks produced during running condition. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 1/2 of the initial value 4 time the initial value twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value twice the initial value 1/4 of the intial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine shape of armature MMF wave is? Saddle shape. Triangular and directed towards main pole. Peaky in nature. Triangular and directed towards brush axis. Saddle shape. Triangular and directed towards main pole. Peaky in nature. Triangular and directed towards brush axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Ke is eddy current constant, Kf is form factor, f is supply frequency, Bm maximum flux density in core of transformer, the expression of eddy current loss in transformer, is given by Kef2Kf2Bm2. Kef2KfBm2. KefKf2Bm2. Kef2Kf2Bm. Kef2Kf2Bm2. Kef2KfBm2. KefKf2Bm2. Kef2Kf2Bm. ANSWER DOWNLOAD EXAMIANS APP