41. In the hysteresis cycle, the value of H needed to make the intensity of
magnetization Zero is called :
(A) Retentivity
(B) Coercive force
(C) Lorentz force
(D) Eddy current force
42. How Basically, which of the following motors are not self-starting?
(A) 3-phase induction motor & 3-phase synchronous motor
(B) 1-phase induction motor & 3-phase synchronous motor
(C) 1-phase induction motor & 3-phase induction motor
(D) 3-phase induction motor, 3-phase synchronous motor & 1-phase induction motor
43. The meter constant of an energy meter is 1500 rev/kWh; the disc makes 3000 revolutions in a given time for a given load. The energy consumed by the load is :
(A) 4 kWh
(B) 1 kWh
(C) 3 kWh
(D) 2 kWh
44. A voltage of v=141.4 x sin(100πt +30°) is applied across a 20 Ω resistor. The phase difference of current with respect to voltage and its rms value are ______ respectively.
(A) 0° & 7.07 A
(B) 0° & 5.0 A
(C) 30° & 7.07 A
(D) 30° & 5.0 A
45. The turns ratio of an ideal 1-phase transformer is 2. Then the power ratio and frequency ratio are :
(A) 1 and 2 respectively
(B) 2 and 0.5 respectively
(C) 1 and 1 respectively
(D) 2 and 1 respectively