a) Using a flywheel b) Designing the synchronous machine with suitable synchronizing power c) Damped bars d) All of these Ans: (d)
a) Reduces harmonics in the generated voltage b) Reduces the total voltage around the armature coils c) Produces a symmetry in the three phase windings d) Increases Cu of end connections Ans: (b)
a) Two coilsides b) Two conductors c) Four conductors d) Four coilsides Ans: (b)
a) Add mechanical strength to the winding b) Reduce the amount of copper required c) Reduce the harmonics in the generated e.m.f. d) Reduce the size of the machine. Ans: (c)
a) Demagnetizing b) Magnetizing c) Cross-magnetizing d) Both magnetizing and cross-magnetizing. Ans: (a)
a) The reduction in terminal voltage when alternator is loaded b) The variation of terminal voltage under the conditions of maximum and minimum excitation c) The increase in terminal voltage when load is thrown off d) The change in terminal voltage from lagging power factor to leading power factor. Ans: (c)
a) Low noise b) Increased inductance c) Suppression of harmonics d) Reduced eddy currents. Ans: (c)
a) The machines will burn b) Both machines will stop c) Synchronising torque will be produced to restore further synchronism d) None of these Ans: (c)
a) Speed of the exciter b) Number of poles c) Exciter current d) Strength of the magnetic field. Ans: (d)
a) Improves cooling by better circulation of air. b) Saves copper use in windings c) Reduces the total voltage around the armature coils d) Suppresses the harmonics in generated emf Ans: (c)
a) To meet iron losses b) To meet copper losses c) To meet all no load losses d) To produce induced emf in armature winding. Ans: (c)
a) Change its frequency. b) Change its power c) Change its load d) Reduce its speed 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 |