Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 1130 r.p.m. 963.8 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. 1130 r.p.m. 963.8 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is lagging power factor None of these unity power factor leading power factor lagging power factor None of these unity power factor leading power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the commutator pitch? Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the back end of the armature. Number of conductors spanned by one coil at the front end of the armature. The distance between the staring of first coil and its next successive coil Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the back end of the armature. Number of conductors spanned by one coil at the front end of the armature. The distance between the staring of first coil and its next successive coil ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If iron loss and full load copper loss of any transformer are denoted by Pi and Pc, then the load corresponding to maximum efficiency is given by (Pi / Pc)2 × full Load. (Pi / Pc) × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc)1.6 × full Load. (Pi / Pc)2 × full Load. (Pi / Pc) × full Load. (Pi / Pc)0.5 × Full Load. (Pi / Pc)1.6 × full Load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides a large starting torque. reduced starting torque. low noise. higher efficiency. a large starting torque. reduced starting torque. low noise. higher efficiency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 ANSWER DOWNLOAD EXAMIANS APP