## electrical

### Electrostatics and Capacitance MCQ With Answers Page - 2

1.
 The sparking between two electrical contacts can be reduced by inserting a A Capacitor in parallel with contacts B Capacitor in series with each contacts C Resistance in line D None of the above Answer : A Explanation :
2.
 In the case of lossy capacitor, its series equivalent resistance value will be A small B Very small C Large D Zero Answer : C Explanation :
3.
 The power dissipated at a pure capacitor is A Zero B Proportional to applied voltage C Proportional to value of capacitance D Both (b) and (c) Answer : A Explanation :
4.
 In a capacitor circuit A A steady value of applied voltage causes discharge B An increase in applied voltage makes a capacitor charge C Decrease in applied voltage makes a capacitor charge D None of the above Answer : B Explanation :
5.
 When a dielectric slab is introduced in a parallel plate capacitor, the potential difference between plates will A Remain unchanged B Decrease C Increase D Become zero Answer : B Explanation :
6.
 Capacitance increase with A Increase in plate area and decrease the distance between the plates B Increase in plate area and distance between the plates C decrease in plate area and value of the applied voltage D reduction in plate area and distance between the plates Answer : A Explanation :
7.
 A capacitor consists of A Two insulators separated by a conductor B Two conductors separated by a insulator C Two insulators only D Two conductors only Answer : B Explanation :
8.
 A gang condenser is a A Polarised capacitor B Variable capacitor C Ceramic capacitor D None of the above Answer : B Explanation :
9.
 A paper capacitor is usually available in the form of A Tubes B Rolled foil C Disc D Meshed plates Answer : B Explanation :
10.
 Air capacitor is generally available in the range A 10 to 400 Pf B 1 to 20 Pf C 100 to 900 Pf D 20 to 100 Pf Answer : A Explanation :
11.
 The unit of capacitance is A Hennery B Ohm C Farad D Farad/m Answer : C Explanation :
12.
 A capacitor charged 200 V has 2000 µC of charge. The value of capacitance will be A 10 F B 10 µF C 100 µF D 1000 µF Answer : B Explanation :
13.
 A capacitor in a circuit become hot and ultimately exploded due to wrong connections, which type of capacitor it could be? A Paper capacitor B Ceramic capacitor C Electrolytic capacitor D Any of the above Answer : C Explanation :
14.
 The ratio of electric flux density to electric field intensity is called …… of the medium A Permeability B Permittivity C Reluctance D Capacitance Answer : B Explanation :
15.
 Energy stored in the electric field of a capacitor C when charged from a D.C source voltage V equal to ………. Joules. A ½ CV² B ½ C²V C CV² D C²V Answer : A Explanation :
16.
 The absolute permittivity of a free space is given by A 8.854 x 10-9F/m B 8.854 x 10-10F/m C 8.854 x 10-11F/m D 8.854 x 10-12F/m Answer : D Explanation :
17.
 The relative permittivity of a free space is given by A 1 B 10 C 100 D 1000 Answer : A Explanation :
18.
 Electric field intensity is a …….quantity A Scalar B Vector C Both (a) and (b) D None of the above Answer : B Explanation :
19.
 When 4 volts e.m.f is applied across 1 farad capacitor , it will store energy of A 2 joules B 4 joules C 6 joules D 8 joules Answer : D Explanation :
20.
 With steady D.C voltage from a battery applied to a capacitance, after it charges to the battery voltage, the current in the circuit A Is smaller for the larger values of capacitance B Is greater for larger values of the capacitance C Is zero for any capacitance value D Depends on the current rating of the battery Answer : C Explanation :
21.
 The capacitor preferred for high frequency circuits is A Air capacitor B Mica capacitor C Electrolytic capacitor D None of the above Answer : B Explanation :
22.
 The capacity of a capacitor bank used in power factor correction is expressed in terms of A kW B kVA C kVAR D Volts Answer : C Explanation :
23.
 While testing a capacitor with ohm-meter, if the capacitor shows charging, but the final resistance reading is appreciably less than normal, it can be concluded that the capacitor is A short-circuited B open-circuited C Alright D Leaky Answer : D Explanation :
24.
 If a 6 µF capacitor is charged to 200V, the charge in coulombs will be A 800µC B 900µC C 1200µC D 1600µC Answer : C Explanation :
25.
 Which capacitor will be physically smaller for the same rating? A Ceramic capacitor B Paper capacitor C Both will be equal size D None of the above Answer : A Explanation :
26.
 What is the value of capacitance that must be connected in parallel with 50 pf condenser to make an equivalent capacitance of 150 pF? A 50 pF B 100 pF C 150 pF D 200 pF Answer : B Explanation :
27.
 A mica capacitor and ceramic capacitor both have the same physical dimensions. Which will have more value of capacitance? A Ceramic capacitor B Mica capacitor C Both will have identical value of capacitance D It depends on applied voltage Answer : A Explanation :
28.
 Which of the following material has least value of dielectric constant? A Ceramics B Oil C Glass D Electrolytic Answer : B Explanation :
29.
 Which of the following capacitors have the least value of breakdown voltage? A Mica B Paper C Ceramic D Electrolyte Answer : D Explanation :
30.
 The breakdown voltage of a paper capacitors is usually A 20 to 60 volts B 200 to 1600 volts C 2000 to 3000 volts D More than 10000 volts Answer : B Explanation :
31.
 Dielectric constant for mica is nearly A 200 B 100 C 3 to 8 D 1 to 2 Answer : C Explanation :
32.
 The value of dielectric constant for vacuum is taken as A Zero B 1 C 4 D 10 Answer : B Explanation :
33.
 Which of the following capacitors is marked for polarity? A Air B Paper C Mica D Electrolytic Answer : D Explanation :
34.
 Which of the following capacitor can be used for temperature compensations? A Air capacitor B Ceramic capacitor C Paper capacitor D None of the above Answer : B Explanation :
35.
 Paper capacitor usually have the tolerance of A ± 5 % B ± 10 % C ± 15 % D ± 20 % Answer : B Explanation :
36.
 For closer tolerances which of the following capacitors is usually preferred? A Paper capacitor B Mica capacitor C Ceramic disc capacitor D None of the above Answer : B Explanation :
37.
 The electrostatic force between two charges of one coulomb each and placed at a distance of 0.5 m will be A 36 x 106 N B 36 x 107N C 36 x 108N D 36 x 109N Answer : D Explanation :
38.
 The units of volume charged density are A Coulombs/meter B Coulombs/meter2 C Coulombs/meter3 D Coulombs/meter4 Answer : C Explanation :
39.
 “The surface integral of normal component of the electrical displacement D over any closed surface equals to the charge enclosed by the surface”The above statement is associated with A Gauss’s law B Kirchhoff’s law C Faraday’s law D Lenz’s law Answer : A Explanation :
40.
 The electrons in the dielectric, get detached from the atoms under A High current B High voltage C Variable current D Breakdown Answer : D Explanation :