TEST START
#1. When electric current passes through a metallic conductor, its temperature rises. This is due to
#2. When electric current passes through a bucket full of water, lot of bubbling is observed. This suggests that the type of supply is
#3. The resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other ?
#4. are the materials having electrical conductivity much less than most of the metals but much greater than that of typical insulators.
#5. With rise in temperature the resistance of semi-conductors
#6. Which method can be used for absolute measurement of resistances ?
#7. Heat in a conductor is produced on the passage of electric current due to
#8. If/, R and t are the current, resistance and time respectively, then according to Joule’s law heat produced will be proportional to
#9. The thickness of insulation provided on the conductor depends on
#10. Switching of a lamp in house produces noise in the radio. This is because switching operation produces
#11. Temperature co-efficient of resistance is expressed in terms of
#12. Which one of the following does not have negative temperature co-efficient ?
#13. One newton meter is same as
#14. Which of the following statement is correct ?
#15. If the efficiency of a machine is to be high, what should be low ?
#16. When resistance element of a heater fuses and then we reconnect it after removing a portion of it, the power
#17. Voltage dependent resistors are used
#18. An open resistor, when checked with an ohm-meter reads
#19. Three resistances of 10 ohms, 15 ohms and 30 ohms are connected in parallel. The total resistance of the combination is
#20. For testing appliances, the wattage of test lamp should be
#21. The four bulbs of 40 W each are connected in series swift a battery across them, which of the following statement is true ?
#22. The ratio of mass of proton to that of electron is nearly
#23. A current of 16 amperes divides between two branches in parallel of resistances 8 ohms and 12 ohms respectively. The current in each branch is
#24. The resistance of a conductor varies inversely as
#25. When one leg of parallel circuit is opened out the total current will
#26. A resistance having rating 10 ohms, 10 W is likely to be a
#27. A nichrome wire used as a heater coil has the resistance of 2 £2/m. For a heater of 1 kW at 200 V, the length of wire required will be
#28. The substances which have a large number of free electrons and offer a low resistance are called
#29. Which of the following materials has a negative temperature co-efficient of resistance?
#30. Bulbs in street lighting are all connected in
#31. The weight of an aluminium conductor as compared to a copper conductor of identical cross-section, for the same electrical resistance, is
#32. Three 6 ohm resistors are connected to form a triangle. What is the resistance between any two corners ?
#33. Two lamps 100 W and 40 W are connected in series across 230 V (alternating).Which of the following statement is correct ?
#34. Ohm’s law is not applicable to
#35. An instrument which detects electric current is known as
#36. All of the following are equivalent to watt except
#37. Four wires of same material, the same cross-sectional area and the same length when connected in parallel give a resistance of 0.25 Q. If the same four wires are connected is series the effective resistance will be
#38. Resistance of carbon filament lamp as the applied voltage increases.
#39. Electric current passing through the circuit produces
#40. Two resistances Rl and Ri are connected in series across the voltage source where Rl>Ri. The largest drop will be across
#41. Resistance of a tungsten lamp as applied voltage increases
#42. All good conductors have high
#43. A 3 Q resistor having 2 A current will dissipate the power of
#44. Two bulbs of 500 W and 200 W rated at 250 V will have resistance ratio as
#45. A light bulb draws 300 mA when the voltage across it is 240 V. The resistance of the light bulb is
#46. Voltage dependent resistors are usually made from
#47. Nichrome wire is an alloy of
#48. Out of the following which is an insulating material ?
#49. Ohm’s law is not applicable to
#50. If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes
#51. Which of the following can have negative temperature coefficient ?
#52. In a circuit a 33 Q resistor carries a current of 2 A. The voltage across the resistor is
#53. Which of the following quantities remain the same in all parts of a series circuit ?
#54. The S.I. unit of Power
#55. The filament of an electric bulb is made of
#56. Electric pressure is also called
#57. Three identical resistors are first connected in parallel and then in series. The resultant resistance of the first combination to the second will be
#58. Insulating materials have the function of
#59. In a lamp load when more than one lamp are switched on the total resistance of the load
#60. When a voltage of one volt is applied, a circuit allows one micro ampere current to flow through it. The conductance of the circuit is
#61. Which of the following materials has the least resistivity ?
#62. A closed switch has a resistance of
#63. A glass rod when rubbed with silk cloth is charged because
#64. A field of force can exist only between
#65. Which of the following material has nearly zero temperature co-efficient of resistance?
#66. An electric filament bulb can be worked from
#67. Out of the following which is not a poor conductor ?
#68. International ohm is defined in terms of the resistance of
#69. Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes
#70. The number of electrons in the outer most orbit of carbon atom is
#71. The property of a conductor due to which it passes current is called
#72. The rating of a fuse wire is always expressed in
#73. A 40 W bulb is connected in series with a room heater. If now 40 W bulb is replaced by 100 W bulb, the heater output will
#74. Which of the following statement is true both for a series and a parallel D.C. circuit?
#75. 1 angstrom is equal to
#76. You have to replace 1500 Q resistor in radio. You have no 1500 Q resistor but have several 1000 Q ones which you would connect
#77. Resistance of 220 V, 100 W lamp will be
#78. With rise in temperature the resistance of pure metals
#79. Sparking occurs when a load is switched off because the circuit has high
#80. Whether circuit may be AC. or D.C. one, following is most effective in reducing the magnitude of the current
#81. Two copper conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller crosssectional area has a resistance of 40 ohms the resistance of other conductor will be
#82. In a series circuit with unequal resistances
#83. The condition for the validity under Ohm’s law is that
#84. The minimum charge on an ion is
#85. With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals
#86. The insulation on a current carrying conductor is provided
#87. Which is the best conductor of electricity
#88. The hot resistance of the bulb’s filament is higher than its cold resistance because the temperature co-efficient of the filament is
#89. Varistors are
#90. Two resistors are said to be connected in series when
#91. What will be energy used by the battery if the battery has to drive 6.28 x 1018 electrons with potential difference of 20 V across the terminal ?
#92. If a parallel circuit is opened in the main line, the current
#93. The resistance of a copper wire 200 m long is 21 Q. If its thickness (diameter) is 0.44 mm, its specific resistance is around
#94. In the case of direct current
#95. Conductance is reciprocal of
#96. Current velocity through a copper conductor is
#97. A thermistor has
#98. Conductance : mho ::
#99. The thickness of insulation provided on the conductor depends on
#100. Which of the following statement is true?
#101. The resistance of a few meters of wire conductor in closed electrical circuit is
#102. Resistance of a material always decreases if
#103. It becomes more difficult to remove
#104. A substance whose molecules consist of dissimilar atoms is called
#105. When current flows through heater coil it glows but supply wiring does not glow because
#106. For which of the following ‘ampere second’ could be the unit ?
#107. In an electric kettle water boils in 10 m minutes. It is required to boil the boiler in 15 minutes, using same supply mains
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