ECAT Physics Current Electricity Online Test

1. The resistivity of constant on is Ω m is

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

3. Reciprocal of resistivity is called

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

5. Specific resistance of a wire depends upon

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

 

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

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

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

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

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

12. Thermocouples convert heat energy into

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

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

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

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

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

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

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

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

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

22. The thermistors are usually made of

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

24. Resistively depends upon the resistance of the material of

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

26. Current provided by a battery is maximum when

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

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

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

30. The unit of conductance of a material is

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

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

33. The strength of an magnetic field depends upon the

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

35. 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

36. Photovoltaic cell converts:

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

38. Thermocouples convert:

39. The passage of an electric current produces

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

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

42. Potentiometer is more sensitive than voltmeter, because

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

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

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

46. Kirchhoff’s first rule is also known as

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

48. 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?

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

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

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

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

53. Thermocouple is an arrangement of two different metals

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

55. 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

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

57. 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

58. The wire used in rheostat, is made from

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

60. The resistivity of wire depends upon:

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

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

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

64. 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?

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

66. The graphical representation of Ohms law is

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

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

69. Electrical power dissipation in resistors is given by

70. The value of resistance depends upon

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

72. The resistively ρ of Tungoston in Ωm is

73. The resistivity ρ of copper in Ω m is

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

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

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

77. Resistance of a conductor depends upon

78. The conductivity of a superconductor is

79. Heat energy dissipated in resistors is defined as:

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

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

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

83. If voltage across a resistance doubles

84. The colour coded carbon resistances are made by

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

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

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

88. Internal resistance is the resistance offered by

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

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

91. 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

92. In a voltmeter the conduction takes place due to

93. Ohm’s law describes the mathematical relationship between

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

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

96. 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

97. Internal resistance is the resistance offered by