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| 1. | Which of the following figures showing the electric field lines is (are) correct?
(1) 
(2) 
(3)  |
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(1) only |
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(2) only |
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(3) only |
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All of the above |
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None of the above |
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| 2. | If a test charge is placed at the position  in the figure below, it will accelerate along which direction?
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up |
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down |
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left |
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right |
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at rest |
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| 3. | If a test charge is placed at the position in the figure below, it will accelerate along which direction?
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up |
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down |
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left |
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right |
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at rest |
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| 4. | A small conducting ball is suspended between two metal plates: one is earthed and the other plate is connected to a high voltage supply. What will happen to the ball? |
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It will swing between the two plates. |
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It will travel in circular motion. |
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It will move towards the high potential plate. |
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It will move towards the earthed plate. |
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It will stay at its original position. |
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| 5. | In order to remove the dust on a glass surface, a dry cloth is used to rub the glass surface. Which of the following statements is (are) correct?
(1) The cloth will be charged.
(2) The glass surface will be charged.
(3) The glass surface will still attract dust. |
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(1) and (2) only |
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(2) and (3) only |
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(1) and (3) only |
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All of the above |
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None of the above |
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| 6. | If two charged particles repel each other. The two particles must be |
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both positive. |
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both negative. |
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of the same sign. |
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of opposite sign. |
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carrying equal charges. |
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| 7. | Which of the following statements about transformer is (are) correct?
(1) The input to output voltage ratio is proportional to the ratio of the numbers of turns of the coils.
(2) the input to output voltage ratio is proportional to the ratio of the currents in the coils.
(3) If we add a soft iron core in the coils, the transformer can transform DC voltage. |
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(1) only |
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(2) only |
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(3) only |
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(1) and (2) only |
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(2) and (3) only |
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| 8. | If each of the resistors in the figures below has the same resistance  , which of the following arrangements can give a equivalent equal to ?
(1) 
(2)
(3)  |
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(1) only |
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(2) only |
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(3) only |
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(1) and (2) only |
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(1) and (3) only |
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| 9. | In the figure below, an ammeter  with resistance 0.5  , a bulb  rated as '6 V, 12 W' and a rheostat  set at 2.5 are connected in series with a 9 V battery. Arrange the appliances in descending order of power dissipation. (Neglect the internal resistance of the battery.)
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| 10. | Referring to the last question, what is the actual power dissipation of the bulb? |
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27 W |
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18 W |
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12 W |
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6.75 W |
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4.5 W |
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| 11. | A 1000 W electrical kettle is used to boil 5 litres water. Which of the following statements is (are) correct?
(1) The rate of electrical energy consumed will be lower if there is less water.
(2) the electrical energy consumed by the kettle in 30 minutes is 0.5 kWh.
(3) The heat energy produced by the kettle in 1 second is 1000 J. |
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(1) only |
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(2) only |
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(1) and (2) only |
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(2) and (3) only |
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All of the above |
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| 12. | Referring to the last question, if the efficiency of the kettle is 50%, the time taken to boil water from 25  to 100 is about (given that specific heat capacity of water = 4200  ) |
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3000 hours |
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10 hours |
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1 hour |
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10 minutes |
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30 seconds |
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| 13. | The resistance of a metal rod increases with
(1) temperature
(2) cross section area
(3) length |
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(1) only |
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(2) only |
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(3) only |
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(1) and (2) only |
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(1) and (3) only |
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| 14. | The resistivity of a metal rod depends on
(1) temperature
(2) cross section area
(3) length |
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(1) only |
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(2) only |
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(3) only |
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(1) and (2) only |
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(1) and (3) only |
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| 15. | Which of the following statements about a rheostat is (are) correct?
(1) The working principle of rheostat is to vary its resistance by changing the cross section area of a resistor.
(2) The resistor used in a rheostat is usually a thick copper wire.
(3) A rheostat can be used as a potentiometer. |
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(1) only |
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(2) only |
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(3) only |
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(1) and (2) only |
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(2) and (3) only |
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| 16. | A 10 A circuit breaker is used. Which of the following arrangements will break the circuit? (Given that the domestic voltage supply is 220 V.)
(1) A 1200 W microwave oven in parallel to an 850 W rice cooker.
(2) A 1500 W air conditioner in parallel to a 750 W iron.
(3) A 1000 W television set in parallel to a 10 motor. |
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(1) only |
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(2) only |
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(1) and (2) only |
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(2) and (3) only |
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All of the above |
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| 17. | In a Christmas lightings, 150 bulbs, each of power 10 W, are all connected in parallel to a electric supply of 200 V. Which of the following fuse should be used? |
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1.5 A |
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3 A |
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5 A |
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10 A |
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15 A |
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