a) To increase the tensile strength of the rotor bars and hence strength b) To reduce the magnetic hum and locking tendency of the rotor c) To see the copper used d) Because of easy in fabrication Ans: (b)
a) Adding external resistance to the rotor b) Adding the external inductance to the rotor c) Adding both resistance and inductance to the rotor d) Adding external capacitance to the rotor Ans: (a)
a) The rotor will not run b) The rotor will run at very high speed c) The slip of the motor will be zero d) The torque produced will be very large Ans: (a)
a) true b) false Ans: (a)
a) 0.06 b)0.10 c) 0.04 d) 0.05 Ans: (d)
a) true b) false Ans: (a)
a) T is proportional to V2 b) T is proportional to V c) T is proportional to √V d) T is proportional to V1/4 Ans: (a)
a) 5% in the rotor torque b) 7% in the rotor torque c) 25% in the rotor d) 10% in the rotor torque Ans: (c)
a) At the value of the slip which makes rotor reactance per phase equal to the resistance per phase b) At the value of the slip which makes the rotor reactance half of the rotor resistance c) At the unit value of the slip d) At the zero value of the slip Ans: (a)
a) true b) false Ans: (a)
a) true b) false Ans: (a)
a) hyperbola b)parabola c) straight line d) rectangular parabola Ans: (d)
a) The maximum torque will depend on rotor resistance b) Although the maximum torque does not depend on rotor resistance yet the exact location of maximum torque is depend on it c) The maximum torque will depend on standstill reactance of rotor d) The slip of the induction motor decreases as the torque increases Ans: (b)
a) 1.6% b) 2% c) 1.65% d) 1.1% Ans: (c)
a) true b) false Ans: (a)