ECAT Physics Current Electricity Online Test

1. 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

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

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

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

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

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

 

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

8. The unit of conductance of a material is

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

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

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

12. The wire used in rheostat, is made from

13. If voltage across a resistance doubles

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

15. Resistively depends upon the resistance of the material of

16. Photovoltaic cell converts:

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

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

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

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

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

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

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

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

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

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

27. Reciprocal of resistivity is called

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

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

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

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

32. The thermistors are usually made of

33. 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?

34. Heat energy dissipated in resistors is defined as:

35. The resistivity of wire depends upon:

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

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

38. The passage of an electric current produces

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

40. 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?

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

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

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

44. 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

45. The resistively ρ of Tungoston in Ωm is

46. Current provided by a battery is maximum when

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

48. The graphical representation of Ohms law is

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

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

51. 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

52. The resistivity of constant on is Ω m is

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

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

55. The conductivity of a superconductor is

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

57. Kirchhoff’s first rule is also known as

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

59. Thermocouple is an arrangement of two different metals

60. The resistivity ρ of copper in Ω m is

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

62. The value of resistance depends upon

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

64. Ohm’s law describes the mathematical relationship between

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

66. Thermocouples convert:

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

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

69. Electrical power dissipation in resistors is given by

70. Potentiometer is more sensitive than voltmeter, because

71. Internal resistance is the resistance offered by

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

73. Thermocouples convert heat energy into

74. Resistance of a conductor depends upon

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

76. Specific resistance of a wire depends upon

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

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

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

80. The colour coded carbon resistances are made by

81. 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

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

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

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

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

86. The strength of an magnetic field depends upon the

87. Internal resistance is the resistance offered by

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

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

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

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

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

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

94. 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

95. In a voltmeter the conduction takes place due to

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

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