Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 5.7 ohms. 1.9 ohms. 6 ohms. 2.2 ohms. 5.7 ohms. 1.9 ohms. 6 ohms. 2.2 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is done in speed control of DC motor by field flux control? Any of above. Inserting an additional resistance in the field circuit. Inserting an additional resistance in the armature circuit. Inserting resistance to armature circuit and field circuit. Any of above. Inserting an additional resistance in the field circuit. Inserting an additional resistance in the armature circuit. Inserting resistance to armature circuit and field circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Synchronous condensers are used to improve starting torque All of these improve the power factor reduce hunting improve starting torque All of these improve the power factor reduce hunting ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a stepper motor the detente torque means minimum of the static torque with the phase winding unexcited. 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 excited. minimum of the static torque with the phase winding unexcited. 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 excited. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchorous generator connected to an infinite bus is over excited. Considering only the reactive power from the point view of the system the machine acts as None of these. A resistor. A capacitor. an inductor. None of these. A resistor. A capacitor. an inductor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of DC motor Both back emf as well as line current increase. Back emf falls and line current increase. Both back emf as well as line current fall. Back emf increase but line current falls. Both back emf as well as line current increase. Back emf falls and line current increase. Both back emf as well as line current fall. Back emf increase but line current falls. ANSWER DOWNLOAD EXAMIANS APP
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