a) The size of the machine will increase b) The size of the stator will increase c) Air gap flux is distributed in the tufts and produce ripples in the wave of generated e.m.f. d) None of the above Ans: (c)
a) Salient pole type b) None-salient pole type c) (a) or (b) d) None of the above Ans: (b)
a) True b) False Ans: (b)
a) To prevent hunting only b) To prevent hunting and provide the starting torque c) To maintain proper synchronism d) To provide the starting torque only Ans: (b)
a) True b) False Ans: (b)
a) 3600 rpm b) 3300 rpm c) 3000 rpm d) 1500 rpm Ans: (c)
a) Short pitched coils in the alternators are used to reduce the size of the machines. b) Short pitched coils are used to reduce the harmonics or to eliminate the harmonics from the generated e.m.f. c) Short pitched coils are used to provide accurate phase difference of 120 degree to one phase to other. d) Short pitched coils are used to reduce copper losses. Ans: (b)
a) Total induced e.m.f. is increased b) Total induced voltage is reduced c) Total induced voltage is distorted d) Total induced voltage is more and hence more insulation is required Ans: (b)
a) (vector sum of induced e.m.fs. per coil)/(terminal voltage of the generator) b) (arithmetic sum of induced e.m.fs. per coil)/(vector sum of induced e.m.fs. per coil) c) (vector sum of induced e.m.fs. per coil)/(arithmetic sum of induced e.m.fs. per coil) d) (arithmetic sum of induced e.m.fs. per coil)/(terminal voltage of the generator) Ans: (c)
a) True b) False Ans: (b)
a) 0.96 b) 0.9 c) 0.933 d) 0.966 Ans: (d)
a) True b) False Ans: (a)
a) Demagnetizing b) Cross-magnetizing c) Square waveform d) N phase with current Ans: (b)
a) True b) False Ans: (a)
a) Load power factor is unity b) Load power factor is zero lagging c) Load power factor is zero leading d) Load power factor is 7.0 lagging Ans: (c)
 Multiple Choice Question (MCQ) of Electronics page-17:241. Which of the following statement is true? a) The saturation voltage VCF of silicon transistor is more than germanium transistor. b) The saturation voltage VCE for germanium transistor is more than silicon transistor. c) The saturation voltage VCE for silicon transistor is same as that for germanium. d) The saturation voltage VCE for silicon transistor is lower than germanium transistor. |
Multiple Choice Question (MCQ) of Electronics page-16:226. Which of the following statement is correct? a) Inner electrons are always present in the semiconductor. b) Bound electrons are always present in the semiconductor. c) Free electrons are always present in the semiconductor. d) Inner and bound electrons are always present in the semiconductor. |
Multiple Choice Question (MCQ) of Electronics page-15:211. The materials whose electrical conductivity is usually less than 1 × 106 mho/m are a) Semiconductors b) Conductors c) Insulators d) Alloys |
Multiple Choice Question (MCQ) of Electronics page-14:196. In which of the following device the base resistors are not added in the package but added externally? a) UJT b) CUJT c) PUT d) None of the above |
Multiple Choice Question (MCQ) of Electronics page-13:181. The conduction in JEFT is always by the a) Majority carriers b) Minority carriers c) Holes d) Electrons e) Holes and electrons simultaneously |