MDCAT Physics Current Electricity Online Test

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

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

3. Internal resistance is the resistance offered by

4. The unit of conductance of a material is

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

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

7. In a voltmeter the conduction takes place due to

8. The colour coded carbon resistances are made by

9. 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?

10. Resistance of a conductor depends upon

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

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

13. The thermistors are usually made of

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

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

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

17. Thermocouple is an arrangement of two different metals

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

19. Reciprocal of resistivity is called

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

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

22. Internal resistance is the resistance offered by

23. 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?

24. Thermocouples convert heat energy into

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

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

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

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

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

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

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

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

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

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

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

36. The wire used in rheostat, is made from

37. 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

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

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

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

41. 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

42. Specific resistance of a wire depends upon

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

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

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

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

47. The value of resistance depends upon

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

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

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

51. Potentiometer is more sensitive than voltmeter, because

52. The conductivity of a superconductor is

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

 

54. If voltage across a resistance doubles

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

56. The resistively ρ of Tungoston in Ωm is

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

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

59. Thermocouples convert:

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

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

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

63. Heat energy dissipated in resistors is defined as:

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

65. 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

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

67. Resistively depends upon the resistance of the material of

68. The resistivity of wire depends upon:

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

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

71. 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

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

73. Ohm’s law describes the mathematical relationship between

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

75. The graphical representation of Ohms law is

76. Photovoltaic cell converts:

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

78. Kirchhoff’s first rule is also known as

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

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

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

82. 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

83. The resistivity ρ of copper in Ω m is

84. Electrical power dissipation in resistors is given by

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

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

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

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

89. The strength of an magnetic field depends upon the

90. Current provided by a battery is maximum when

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

92. The resistivity of constant on is Ω m is

93. The passage of an electric current produces

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

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

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

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