Physics Current Electricity Online Mcqs Test

1. If doubling the voltage across a resistor doubles the current through the resistor then

2. Which one is the best material for making connecting wires?

3. A cell of emf 1.56 Volt is connected directly to an ammeter of resistance 0.05Ω. If the current in the circuit is 2.0A, the internal resistance of the cell is

4. The conductivity of a superconductor is

5. If potential difference across the conductor is one volt and one ampere current is flowing, then resistance of the conductor is:

6. The potential difference between head and tail of an electric eel (fish) up to

7. A factory gets its electrical power from a generator two miles away. The wires connecting the generator to the factory terminals have a resistance of 0.04 Ω/miles. When the generator supplies 50 Ampere to the factory, the terminal voltage at the generator is 120 Volts. A voltmeter connected to the factory terminals should then read

8. A certain charge liberates 0.8 g of oxygen. The same charge will liberate, how many g of silver

9. Which one of the following causes production of heat when current is set up in a wire?

10. A wire of resistance 3.0 W is stretched to twice its original length, The resistance of the new wire will be

11. What is the current (I) in the circuit, as shown in the figure.

12. The charge on an electron is known to be 1.6 x 10¯¹⁹ coulomb. In a circuit the current flowing is 1 A. How many electrons will be flowing through the circuit in a second?

13. The reciprocal of the resistance of a conductor is called

14. The colour coded carbon resistances are made by

15. A (100 W, 200 V) bulb is connected to a 160 V power supply. The power consumption would be

16. The electric motors uses the effect of current passing through them is

17. Three resistors of resistance 2, 3 and 6 ohms are connected in parallel, their equivalent resistance is

18. A battery of emf 12V and internal resistance 0.5 is charged by a battery charger which supplied a 132 V d.c. supply using a series resistance of 11.5. What is the terminal voltage of the battery during changing?

19. Every source of current converts some non-electrical energy into

20. Internal resistance is the resistance offered by

21. The wire used in rheostat, is made from

22. The graphical representation of Ohms law is

23. Due to collisions of electrons, with the atoms of conductor, the energy transfer ultimately to the

24. The passage of an electric current produces

25. The emf is the “cause” and potential difference is its

26. What type of temperature coefficient of resistance is thermistors?

27. Potentiometer is more sensitive than voltmeter, because

28. When same current passes for same time through a thick and thin wire

29. A piece of fuse wire melts when a current of 15 ampere flows through it. With this current, if it dissipates 22.5 W, the resistance of fuse wire will be

30. What electromotive force would cause 20 A of current to flow through a 500 Ω resistor?

31. When the temperature of a metallic conductor is increased its resistance:

32. Two electric bulbs of 200 W and 100 W have same voltage. If R₁ and R₂ be their resistance respectively then

33. Thermocouples convert heat energy into

34. The resistivity of wire depends upon:

35. A heater coil rated at (1000 W – 200 V) is connected to 110 volt line. What will be the power consumed?

36. The resistively ρ of Tungoston in Ωm is

37. A 50 volt battery is connected across 10 ohm resistor. The current is 4.5 A. The internal resistance of the battery is

38. A wheat stone bridge is said to be balanced when?

39. A wire of radius r has resistance R. If it is stretched to a wire of r/2 radius, then the resistance becomes

40. Conventional current (l) is due to the motion of:

41. A 60 W bulb operates on 220 V supply. The current flowing through bulb is

42. At ordinary temperature, an increase in temperature increases the conductivity of

43. Internal resistance is the resistance offered by

44. A conducting wire is drawn to double its length. Final resistivity of the material will be:

45. Electrical power dissipation in resistors is given by

46. The drifty velocity of free electrons in a metallic conductor is

47. Power dissipated in the form of ‘V’ and ‘R’ can be determine as:

48. In a voltmeter the conduction takes place due to

49. The colour sequence in a carbon resistor in red, brown, orange and silver. The resistance of resistor is

50. Resistance of wire is r ohms. The wire is stretched to double its length, then its resistance in ohms is

51. The resistance of a conductor increases with the increase in its:

52. Electromotive force is not a force and is measured in

53. Two resistances of 2Ω and 3Ω connected in parallel are attached to a source of 20 V. The current through 3Ω resistance is

54. As the charge flows through the conductor energy is dissipated in the form of:

55. The value of resistance depends upon

56. Reciprocal of resistivity is called

57. Resistively depends upon the resistance of the material of

58. Kirchhoff’s first rule is also known as

59. Heat energy dissipated in resistors is defined as:

60. Photovoltaic cell converts:

61. Two resistances of 2Ω and 3Ω connected in series are attached to a source of 20 V. The potential difference across 3Ω resistance is

62. If 2.2 kilowatt power is transmitted through a 10 ohm line at 22000 volt, the power loss in the form of heat will be

63. High negative temperature coefficient thermistors are very accurate for measuring low temperature near

64. The current through a metallic conductor is due to the motion of

65. Production of heat due to an electric current following through a conductor is given by

66. The electromotive force of a battery or cell is the voltage between its terminals when:

67. In liquids and gases, the current is due to the motion of:

68. A wire of uniform area of cross-section A length La and resistance R is cut into two parts. Resistivity of each part

69. The resistivity of constant on is Ω m is

70. Thermocouple is an arrangement of two different metals

71. A car battery has e.m.f. 12 volt and internal resistance 5 x 10¯² ohm. If it draws 60 ampere current, the terminal voltage of the battery will be

72. A 100 watt bulb is operated by 200 volt, the current flowing through the bulb is:

73. Specific resistance of a wire depends upon

74. The chemical changes produced during the electrolysis are due to chemical effect of

75. The resistivity ρ of copper in Ω m is

76. In the figure a carbon resistor has bands of different colours on its body as mentioned in. the value of the resistance is

77. In the circuit each of the three resistances has a resistance 30Ω. The potential difference across R₁ is

 

78. Ohm’s law describes the mathematical relationship between

79. If the voltage across a fixed value of resistance is increased five times, what does the current do?

80. The thermistors are usually made of

81. A ten ohm electric heater operates on a 110 V line. Calculate the rate at which it develops heat in watts:

82. Current provided by a battery is maximum when

83. In carbon colour coded resistance, the fourth Gold ban indicates the tolerance is

84. In a house circuit, all electrical appliances are connected in parallel to each other between the line and neutral wires to get:

85. A conductor which obeys Ohm’s law is called

86. If the resistance in a circuit with constant voltage increases, the current will

87. If voltage across a resistance doubles

88. Terminal potential difference of a battery is greater than its emf when

89. When the resistors are connected in series, the equivalent resistance is always:

90. The resistance of the given conductor can be increased by

91. The unit of conductance of a material is

92. The strength of an magnetic field depends upon the

93. A wire having very high value of conductance is said to be

94. Thermocouples convert:

95. The potential difference across each resistance in series combination, if the resistances are different, is

96. Resistance of a conductor depends upon

97. Cause of heat production in a current carrying conductor is