ECAT Physics Current Electricity Online Test

1. Photovoltaic cell converts:

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

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

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

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

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

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

8. If voltage across a resistance doubles

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

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

11. The conductivity of a superconductor is

12. Internal resistance is the resistance offered by

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

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

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

16. In a voltmeter the conduction takes place due to

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

18. The resistively ρ of Tungoston in Ωm is

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

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

21. Heat energy dissipated in resistors is defined as:

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

23. 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?

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

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

26. The resistivity ρ of copper in Ω m is

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

28. The unit of conductance of a material is

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

30. Current provided by a battery is maximum when

31. Specific resistance of a wire depends upon

32. The colour coded carbon resistances are made by

33. The wire used in rheostat, is made from

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

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

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

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

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

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

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

41. The resistivity of wire depends upon:

42. Resistance of a conductor depends upon

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

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

45. The value of resistance depends upon

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

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

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

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

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

51. The thermistors are usually made of

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

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

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

55. Reciprocal of resistivity is called

56. The strength of an magnetic field depends upon the

57. Thermocouples convert heat energy into

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

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

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

61. The graphical representation of Ohms law 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. The resistance of a conductor increases with the increase in its:

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

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

66. Electrical power dissipation in resistors is given by

67. Internal resistance is the resistance offered by

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

 

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

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

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

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

73. 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?

74. 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

75. 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

76. 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

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

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

79. Resistively depends upon the resistance of the material of

80. Potentiometer is more sensitive than voltmeter, because

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

82. The resistivity of constant on is Ω m is

83. Ohm’s law describes the mathematical relationship between

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

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

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

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

88. Thermocouples convert:

89. The passage of an electric current produces

90. Kirchhoff’s first rule is also known as

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

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

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

94. Thermocouple is an arrangement of two different metals

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

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

97. 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