Electrical Machines Find the number of poles required, when the frequency is 50Hz and speed of the motor is 500 rpm? 12 10 5 24 12 10 5 24 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor has a rotor resistance of 0.002 Ω / phase. If the resistance is increased to 0.004 Ω / phase then the maximum torque will increase by 100% increase by 200% reduced to half remain unaltered increase by 100% increase by 200% reduced to half remain unaltered ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Rotor mmf wave. Rotor winding. Both rotor and stator winding. Stator winding. Rotor mmf wave. Rotor winding. Both rotor and stator winding. Stator winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is 768 V 192 V 384 V 96 V 768 V 192 V 384 V 96 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 38% 68% 40% 60% 38% 68% 40% 60% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a stepper motor the detente torque means maximum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding excited. maximum of the static torque with the phase winding excited. maximum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding excited. maximum of the static torque with the phase winding excited. ANSWER DOWNLOAD EXAMIANS APP