Physics Current Electricity Online Mcqs Test

1. 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

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

3. The strength of an magnetic field depends upon the

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

5. 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?

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

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

8. The resistivity of constant on is Ω m is

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

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

 

11. The resistivity of wire depends upon:

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

13. The value of resistance depends upon

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

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

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

17. Thermocouples convert:

18. Kirchhoff’s first rule is also known as

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

20. 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

21. The unit of conductance of a material is

22. 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

23. The colour coded carbon resistances are made by

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

25. 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

26. Electrical power dissipation in resistors is given by

27. Thermocouple is an arrangement of two different metals

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

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

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

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

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

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

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

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

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

37. 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

38. The thermistors are usually made of

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

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

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

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

43. The graphical representation of Ohms law is

44. The resistivity ρ of copper in Ω m is

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

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

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

48. Heat energy dissipated in resistors is defined as:

49. Current provided by a battery is maximum when

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

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

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

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

54. Thermocouples convert heat energy into

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

56. Internal resistance is the resistance offered by

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

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

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

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

61. The passage of an electric current produces

62. The conductivity of a superconductor is

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

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

65. Resistively depends upon the resistance of the material of

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

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

68. If voltage across a resistance doubles

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

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

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

72. Potentiometer is more sensitive than voltmeter, because

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

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

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

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

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

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

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

80. Reciprocal of resistivity is called

81. In a voltmeter the conduction takes place due to

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

83. The wire used in rheostat, is made from

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

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

86. Ohm’s law describes the mathematical relationship between

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

88. The resistively ρ of Tungoston in Ωm is

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

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

91. Specific resistance of a wire depends upon

92. Photovoltaic cell converts:

93. 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?

94. Resistance of a conductor depends upon

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

96. Internal resistance is the resistance offered by

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