Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 6 Ω 1.9 Ω 2.2 Ω 5.7 Ω 6 Ω 1.9 Ω 2.2 Ω 5.7 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When two DC series motors are connected in parallel, the resultant speed is less than normal speed. zero. normal speed. more than normal speed. less than normal speed. zero. normal speed. more than normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following statements is/are correct statements? All of these EMF per turn in HV winding is less than EMF per turn in LV winding EMF per turn in both the windings are equal EMF per turn in HV winding is more than EMF per turn in LV winding All of these EMF per turn in HV winding is less than EMF per turn in LV winding EMF per turn in both the windings are equal EMF per turn in HV winding is more than EMF per turn in LV winding ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, which of these parameters remain the same whether it runs as a DC motor or a DC generator? Armature current. Induced emf. Mechanical power. Can not be determined. Armature current. Induced emf. Mechanical power. Can not be determined. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value remain the same as the original changes to 0.5 times the original value changes to three times the original value changes to 1.5 times the original value remain the same as the original changes to 0.5 times the original value changes to three times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between the yoke and armature is dc machine is kept very small All of these to achieve a stronger magnetic field. to avoid over heating. to avoid locking of the armature. All of these to achieve a stronger magnetic field. to avoid over heating. to avoid locking of the armature. ANSWER DOWNLOAD EXAMIANS APP
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