Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 3.05+j5.08 ohms 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms 3.05+j5.08 ohms 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a DC series motor is Proportional to field current. Proportional to the square of the armature current. Proportional to the armature current. Inversely proportional to the armature current. Proportional to field current. Proportional to the square of the armature current. Proportional to the armature current. Inversely proportional to the armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Stability of a synchronous motor ---------- with the increase in excitation. remains unaffected any of the above decreases increases remains unaffected any of the above decreases increases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low viscosity. high viscosity. low resistivity. low BDV. low viscosity. high viscosity. low resistivity. low BDV. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator results in sparking trouble. reduces inter poles flux density. reduces generator emf. increases armature speed. results in sparking trouble. reduces inter poles flux density. reduces generator emf. increases armature speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. ANSWER DOWNLOAD EXAMIANS APP