Electrical Machines If the no-voltage release in a DC motor starter fails to operate on failure of supply, on resumption of supply the motor will start automatically without trouble. not start automatically. develop very low starting torque. get damaged. start automatically without trouble. not start automatically. develop very low starting torque. get damaged. 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, 2 and 3 1 and 3 1, 3 and 5 1, 2, 3 and 5 1, 2 and 3 1 and 3 1, 3 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φf E ∝ f/φ E ∝ 1/(φf) E ∝ φ/f E ∝ φf E ∝ f/φ E ∝ 1/(φf) E ∝ φ/f ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction in DC generators will result in open circuit. reduction in generated emf. increase in slip. short circuit. open circuit. reduction in generated emf. increase in slip. short circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor the torque is proportional to P² 1/P 1/P² Power P P² 1/P 1/P² Power P ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Width of a carbon brush should be equal to less than the width of commutator segment. the width of the 1 to 2 commutator segment. the width of the 2 to 3 commutator segment. the width more than 3 commutator segment. less than the width of commutator segment. the width of the 1 to 2 commutator segment. the width of the 2 to 3 commutator segment. the width more than 3 commutator segment. ANSWER DOWNLOAD EXAMIANS APP