MDCAT Physics Current Electricity Online Test

1. The thermistors are usually made of

2. Photovoltaic cell converts:

3. Heat energy dissipated in resistors is defined as:

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

5. Current provided by a battery is maximum when

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

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

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

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

10. 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?

11. The unit of conductance of a material is

12. Internal resistance is the resistance offered by

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

14. Thermocouple is an arrangement of two different metals

15. Thermocouples convert:

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

17. 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

18. Internal resistance is the resistance offered by

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

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

21. Reciprocal of resistivity is called

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

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

24. The graphical representation of Ohms law is

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

26. Electrical power dissipation in resistors is given by

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

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

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

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

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. Specific resistance of a wire depends upon

33. The resistivity of constant on is Ω m is

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

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

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

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

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

39. The resistivity ρ of copper in Ω m is

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

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

42. The conductivity of a superconductor is

43. Potentiometer is more sensitive than voltmeter, because

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

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

46. 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

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

48. The resistively ρ of Tungoston in Ωm is

49. 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

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

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

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

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

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

55. Resistively depends upon the resistance of the material of

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

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

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

59. The colour coded carbon resistances are made by

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

61. 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

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

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

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

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

66. The value of resistance depends upon

67. The wire used in rheostat, is made from

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

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

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

71. Kirchhoff’s first rule is also known as

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

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

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

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

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

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

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

79. Thermocouples convert heat energy into

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

81. The passage of an electric current produces

82. 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?

83. 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

84. The strength of an magnetic field depends upon the

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

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

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

88. If voltage across a resistance doubles

89. Ohm’s law describes the mathematical relationship between

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

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

92. Resistance of a conductor depends upon

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

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

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

 

96. In a voltmeter the conduction takes place due to

97. The resistivity of wire depends upon: