Electrical Machines Counter emf of a DC motor exceeds supply voltage aids applied voltage. helps in energy conversion. regulates its armature voltage. exceeds supply voltage aids applied voltage. helps in energy conversion. regulates its armature voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 2, 3 and 5 1, 3 and 5 1, 2 and 3 1 and 3 1, 2, 3 and 5 1, 3 and 5 1, 2 and 3 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole, 50 Hz induction motor 4 % slip, calculate frequency of the rotor emf? 2 Hz. 50 Hz. 10 Hz. 3 Hz. 2 Hz. 50 Hz. 10 Hz. 3 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce hysteresis loss. to reduce eddy current loss. to provide better flux linkage. to reduce mechanical losses. to reduce hysteresis loss. to reduce eddy current loss. to provide better flux linkage. to reduce mechanical losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 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 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 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 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 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In escalator which motor is used? 1 - φ IM. DC shunt motor. 3 - φ IM. Universal motor. 1 - φ IM. DC shunt motor. 3 - φ IM. Universal motor. ANSWER DOWNLOAD EXAMIANS APP