Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/2. PN/3000. PN/60. PN/120. PN/2. PN/3000. PN/60. PN/120. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of motors are preferred in lifts? None of these DC shunt motors. DC compound motors. DC series motors. None of these DC shunt motors. DC compound motors. DC series motors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC generator rotates at 1500 rpm. How many times in a second, will the emf induced in each armature conductor changes its direction? 750. 100. 500. 200. 750. 100. 500. 200. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 1, 2, 5 1, 2, 3, 4 1, 3, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature of DC machine is made of insulating material. non-ferrous material. silicon steel. conducting material. insulating material. non-ferrous material. silicon steel. conducting material. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor will remains same. Decrease.d none of these. increase. remains same. Decrease.d none of these. increase. ANSWER DOWNLOAD EXAMIANS APP
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