31. Capacitance of a capacitor

- Increases with increases in overlapping area of plates
- Increases with increases in relative permittivity of the dielectric
- Increases with decreases in distance between the plates
- All of these

32. The energy required to charge a 10 F capacitor to 100 V is

- 0.1 J
- 5 x 10
^{4}J - 5 x 10
^{-9}J - 10 x 10
^{-9}J

32. If four 80 micro farad capacitors are connected in series, the net capacitance is

- 20 micro farads
- 40 micro farads
- 160 micro farads
- 320 micro farads

33. Capacitance, Voltage and Charge are related as

- C = QV
- Q = CV
- V = QC
- None of these

34. Capacitors with solid dielectric materials are used because

- they give a reduced dielectric loss
- they are smaller in size as compared with air capacitors
- they have a lower capacitance value is with air capacitors
- none of these

35. A circuit component that opposes the change in circuit voltage is

- resistance
- capacitance
- inductance
- All of these

36. The Energy stored in a Capacitor can be represented as

- CV
^{2}/2 - V
^{2}/2C - C
^{2}V/2 - None of these

37. A coil would behave as

- An inductor at high frequencies
- A capacitor at very low frequencies
- A resistor at high frequencies
- A capacitor at very high frequencies

38. An air-filled parallel plate capacitor made of square plates, each 10 cm x 10 cm, has a capacitance C. If the plates are reduced to 2.5 cm x 2.5 cm, what would be the new capacitance?

- C/8
- C/4
- C/32
- C/16

39. A capacitor capable of storing 1 J of energy at 100 V dc supply. The value of capacitance will be?

- 100 μF
- 200 μF
- 50 μF
- 400 μF

40. The power consumed by a pure capacitor is

- 1 W
- 0.5 W
- ∞ W
- 0 W

41. Two capacitors of 2 μF and 3 μF are connected in series across 10 V. The potential difference across the 2 μF capacitor will be

- 4 V
- 6 V
- 10 V
- 0 V

42. An ideal voltage source will charge an ideal capacitor.

- in Infinite time
- Exponentially
- Instantaneously
- None of these

43. A capacitor is charged by a constant current of 2 mA and results in a voltage increase of 12 V at 10 sec interval. The value of capacitance is

- 0.75 milli Farad
- 24 milli Farad
- 1.67 milli Farad
- 12 milli Farad

44. The electrical capacitance is analogous of

- Fluid flow
- Thermal resistance
- Inertia
- Spring

45. The capacitance of a parallel plate capacitor is not affected by

- Thickness of conducting plates
- Area of the conducting plates
- Distance separating the plates
- Nature of the dielectric between the plates

46. An electrolyte capacitor can be used for

- DC only
- AC only
- Both
- None

47. The maximum energy (W) stored in a capacitive circuit is

(Where C = capacitance of the circuit and E = potential applied)

- W=CE
^{2} - W = C
^{2}E - W= 1/2 (CE
^{2}) - W = 1/2 (C
^{2}E)

48. When a current source is connected to a capacitor,

- The displacement current flows through the capacitor
- No current flows through the capacitor
- The conduction current flows through the capacitor
- Current can not be quantified as displacement current or conduction

49. Two capacitors of capacitances 3 μF and 6 μF in series will have a total capacitance of

- 9 μF
- 2 μF
- 18 μF
- 24 μF

50. A capacitor opposes

- Change in current
- Change in voltage
- Both change in current and voltage
- None of these

51. If three capacitors C_{1}, C_{2} and C_{3} of values of 1 μF, 2 μF and 4 μF respectively are in series and connected across a potential of 230 V, then charge of each capacitor is

- 110 x 10
^{-6}C - 121 x 10
^{-6}C - 131 x 10
^{-6}C - 161 x 10
^{-6}C

52. Which of the following statement is incorrect?

- The leakage resistance of ceramic capacitor is generally high.
- The stored energy in a capacitor decreases with reduction in value of capacitance
- The stored energy in a capacitor increases with applied voltage
- A wire cable has distributed capacitance between the conductors

53. A voltage source (V) is connected across a capacitor (C) through a switch to form a circuit. At the instant, the switch is closed

- An infinite current flows through capacitor C after some time
- An infinite current flows through the capacitor C instantaneously
- No current will flow through the capacitor but a voltage V will appear across the capacitor.
- None of the other options

54. If an uncharged capacitor is connected to an energy source then

- The capacitor acts as an open circuit
- Current will start flowing in the capacitor in due course of time
- Current will flow instantaneously
- None of the other options

55. A variable capacitance is one whose capacitance

- Changes with time
- Changes with temperature
- Changes with voltage
- Can be changed

56. If a capacitor stores 100 μC charge at 10 volts, the capacitance value is

- 100 μF
- 1000 μF
- 10 μF
- 1 μF

57. Two 10 μF capacitors are connected in parallel. What is the equivalent capacitor value?

- 40 μF
- 25 μF
- 20 μF
- 5 μF

58. During dielectric breakdown of a capacitor

- electrons cease to move from one plate to another
- permanent conduction path is established between plates
- dielectric stored energy rendering plates charge-less
- electrons get scattered

59. A capacitor has two

- conductors separated by a dielectric
- insulators separated by a conductor
- two insulators separated by air medium only
- two conductors only

60. If a capacitor of 200 μF is charged to a potential of 100 V, then the stored energy (in watts) record is

- 200
- 100
- 50
- 1