Electrical Machines If residual magnetism of a shunt generator is destroyed accidentally it may be restored by connecting its shunt field to an AC source. to a DC source. in reverse. to earth. to an AC source. to a DC source. in reverse. to earth. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf is same as long as the flux density in the air gap remains the same. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is less with wave winding than with lap winding. Armature emf is more with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is less with wave winding than with lap winding. Armature emf is more with wave winding than with lap winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machines have highest power factor with respect to magnetizing current? Semi closed slot type machine. Any of the above. Open slot type machines. Closed slot type machines. Semi closed slot type machine. Any of the above. Open slot type machines. Closed slot type machines. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 94% 96% 95% 92% 94% 96% 95% 92% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator the actual flux distribution depends upon clearance between tips of the adjacent pole shoes. shape of the pole shoe. size of air gap. all of above. clearance between tips of the adjacent pole shoes. shape of the pole shoe. size of air gap. all of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 2 X 1012 Ω - cm at 27°C and 0.2 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 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 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 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 ANSWER DOWNLOAD EXAMIANS APP