Multiple Choice Questions(MCQ) on Electrostatics and Capacitance
1. The lines of force due to charged particles are
(a) always straight
(b) always curved
(c) sometimes curved
(d) none of the above
Ans: b
2. The electric field at a point situated at a distance d from straight charged conductor is
(a) proportional to d
(b) inversely proportional to d
(c) inversely proportional to d
(d) none of the above
Ans: b
3. For making a capacitor, it is better to select a dielectric having
(a) low permittivity
(b) high permittivity
(c) permittivity same as that of air
(d) permittivity slightly more than that of air
Ans: b
4. An electrolytic capacitor can be used for
(a) D.C. only
(b) AC. only
(c) both D.C. as well as A.C.
Ans: a
5. Which of the following is not a vector ?
(a) Linear momentum
(b) Angular momentum
(c) Electric field
(d) Electric potential
Ans: d
6. The dissipation factor of a good dielectric is of the order of
(a) 0.0002
(b) 0.002
(c) 0.02
(d) 0.2
Ans: a
7. Which of the following materials has the highest value of dielectric constant?
(a) Glass
(b) Vacuum
(c) Ceramics
(d) Oil
Ans: c
8. Which of the following capacitors will have the least variation ?
(a) Paper capacitor
(b) Ceramic capacitor
(c) Silver plated mica capacitor
(d) None of the above
Ans: c
9. Which of the following capacitors has relatively shorter shelf life ?
(a) Mica capacitor
(b) Electrolytic capacitor
(c) Ceramic capacitor
(d) Paper capacitor
Ans: b
10. The sparking between two electrical contacts can be reduced by inserting a
(a) capacitor in parallel with contacts
(b) capacitor in series with each contact
(c) resistance in line
(d) none of the above
Ans: a
11. In a capacitive 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
Ans: b
12. A gang condenser is a
(a) polarised capacitor
(b) variable capacitor
(c) ceramic capacitor
(d) none of the above
Ans: b
13. Air capacitors are 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
Ans: a
14. 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
Ans: d
15. Which of the following material has least value of dielectric constant ?
(a) Ceramics
(b) Oil
(c) Glass
(d) Paper
Ans: b
16. Which of the following capacitors will have the least value of breakdown voltage ?
(a) Mica
(b) Paper
(c) Ceramic
(d) Electrolytic
Ans: d
17. Which of the following capacitors is marked for polarity ?
(a) Air
(b) Paper
(c) Mica
(d) Electrolytic
Ans: d
18. Which of the following capacitors can be used for temperature compensation ?
(a) Air capacitor
(b) Ceramic capacitor
(c) Paper capacitor
(d) None of the above
Ans: b
19. Paper capacitors usually have a tolerance of
(a) ± 5%
(b) ± 10%
(c) ± 15%
(d) ± 20%
Ans: b
20. Dielectric strength of mica is
(a) 10 to 20 kV/mm
(b) 30 to 50 kV/mm
(c) 50 to 200 kV/mm
(d) 300 to 500 kV/mm
Ans: c
21. The dielectric constant (relative permittivity) of glass is given by
(a) 0.1 to 0.4
(b) 0.5 to 1.0
(c) 2.0 to 4.0
(d) 5 to 100
Ans: d
22. capacitors can be used only for D.C.
(a) Air
(b) Paper
(c) Mica
(d) Electrolytic
Ans: d
23. The inverse of capacitance is called
(a) reluctance
(b) conductance
(c) susceptance
(d) elastance
Ans: d
24. When the dielectric is homogeneous,the potential gradient is
(a) uniform
(b) non-uniform
(c) zero
(d) any of the above
Ans: a
25. The relative permittivity has the following units
(a) F/m
(b) m/F
(c) Wb/m
(d) no units
Ans: d
26. The phenomenon of an uncharged body getting charged merely by the nearness of a charged body is known as
(a) pholoelectric effect
(b) chemical effect
(c) magnetic effect
(d) induction
Ans: d
27. A unit tube of flux is known as ...... tube
(a) Newton
(b) Faraday
(c) Michale
(d) None of the above
Ans: b
28. The value of E within the field due to a point charge can be found with the help of
(a) Faraday’s laws
(b) Kirchhoff s laws
(c) Coulomb’s laws
(d) none of the above
Ans: c
29. Electric displacement is a______quantity.
(a) scalar
(b) vector
(c) both of the above
(d) none of the above
Ans: b
30 The time constant of R-C circuit may also be defined as the time during which the charging current falls to ______ percent of its initial maximum value,
(a) 37
(b) 42
(c) 63
(d) 73
Ans: a
31. 1 volt/meter is same as
(a) 1 meter/coulomb
(b) 1 newton meter
(c) 1 newton/meter
(d) 1 joule/coulomb
Ans: c
32. The bridge used for the measurement of the value of the capacitance is
(a) Wien’s bridge
(b) Wheatstone bridge
(c) Schering bridge
(d) Hay’s bridge
Ans: c
33. Out of the following capacitors of identical rating which one will have the smallest dimensions ?
(a) Aluminium foil capacitor
(b) Mica capacitor
(c) Ceramic capacitor
(d) Paper capacitor
Ans: c
34. An uncharged conductor is placed near a charged conductor, then
(a) the uncharged conductor gets charged by conduction
(b) the uncharged conductor gets charged by induction and then attracted towards the charging body (c) the uncharged conductor is attracted first and then charged by induction
(d) it remains as such
Ans: b
35. The presence of an uncharged conductor near a charged one increases the
(a) charge of the charged conductor
(b) capacity of the charged conductor
(c) potential of the charged conductor
(d) all of the above
Ans: b
36. Paper condenser is
(a) always polarised
(b) usually of fixed value
(c) electrolytic condenser
(d) a variable condenser
Ans: b
37. An electrolytic capacitor is generally made to provide
(a) low capacitance
(b) fixed capacitance
(c) variable capacitance
(d) large value of capacitance
Ans: d
38. The minimum value of potential gradient in a cable occurs in
(a) insulation
(b) conductor
(c) outer sheath
(d) uniformly all over
Ans: a
39. Dielectric strength of medium
(a) increases with rise in temperature
(b) increases with moisture content
(c) is same for all insulating materials
(d) none of the above
Ans: d
40. When a dielectric is placed in an electric field the field strength
(a) decreases
(b) increases
(c) reduces to zero
(d) remain unchanged
Ans: a
41. To prevent the generation of static charges on rubber or flat leather
(a) surface is moistened
(b) conductive dressing is done
(c) oil compound dressing is done
(d) talcum powder is sprayed on the surface
Ans: b
42. Which of the following capacitor is preferred in case of single phase motor ?
(a) Mica capacitor
(b) Paper capacitor
(c) Electrolytic capacitor
(d) Ceramic capacitor
Ans: c
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#MCQ on electrical engineering
#electrical engineering mcq with answer
#Electrostatics and Capacitance mcq.
Tq sir good
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