Electrical Machines The starting resistance of DC motor is generally Infinitely large. Low. 1000 ohms. around 500 ohms. Infinitely large. Low. 1000 ohms. around 500 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flux density under leading pole tips in case of generator will None of these decrease either increase or decrease increase None of these decrease either increase or decrease increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides a large starting torque. low noise. reduced starting torque. higher efficiency. a large starting torque. low noise. reduced starting torque. higher efficiency. 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 avoid over heating. to avoid locking of the armature. to achieve a stronger magnetic field. All of these to avoid over heating. to avoid locking of the armature. to achieve a stronger magnetic field. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 4 X 1012 Ω - cm at 27°C and 0.4 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 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 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 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 2166.67V, 230 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. ANSWER DOWNLOAD EXAMIANS APP