Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.443. 0.649. 0.512. 0.573. 0.443. 0.649. 0.512. 0.573. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In the V curve shown in figure below for a synchronous motor, the parameter of Y and X coordinates are, respectively Power factor and field current. Torque and field current. Armature current and field current. Armature current and torque. Power factor and field current. Torque and field current. Armature current and field current. Armature current and torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hunting in a synchronous motor takes place when load varies. when supply voltage fluctuates. when power factor is unity. motor is under loaded. when load varies. when supply voltage fluctuates. when power factor is unity. motor is under loaded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V dc series generator is driven at its rated speed. The no-load voltage across its armature terminals would be somewhat more than 230 V 230 V 6 V somewhat less than 230 V somewhat more than 230 V 230 V 6 V somewhat less than 230 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.1 Ω 15.9 Ω 31.9 Ω 31.1 Ω 15.1 Ω 15.9 Ω 31.9 Ω 31.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of conductor of a DC motor can be determined by Fleming's left hand rule. Fleming's right hand rule. Lenz's law. Ampere law. Fleming's left hand rule. Fleming's right hand rule. Lenz's law. Ampere law. ANSWER DOWNLOAD EXAMIANS APP
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