11. Which one of the following statements is correct ? The space surrounding a charge in uniform motion has

1. 1. Only an electric held

   
   
   

   2. Only a magnetic fields

   
   
   

   3. Both electric and magnetic fields

   
   
   

   4. Neither an electric field nor a magnetic field

   
   
   

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   N/A

   Correct Option: C

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12. Two electric fans p and 2 p watt respectively are connected in series. What is the power of the combination in watt ?

1. 1. p

   
   
   

   2. 3 p

   
   
   

   3. 2p / 3

   
   
   

   4. 3 p / 2

   
   
   

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   N/A

   Correct Option: C

   N/A

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13. Indiscriminate disposal of used fluorescent electric lamps causes mercury pollution in the environment. Why is mercury used in the manufacture of these lamps?

1. 1. A mercury coating on the inside of the lamp makes the light bright white

   
   
   

   2. When the lamp is switched on, the mercury in the lamp causes the emission of ultra-violet radiations

   
   
   

   3. When the lamp is switched on, it is the mercury which converts the ultra-violet energy into visible light

   
   
   

   4. None of the statement given above is correct about the use of mercury in the manufacture of fluorescent lamps

   
   
   

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   N/A

   Correct Option: B

   N/A

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14. A superconductor exhibits

1. 1. Paramagnetism

   
   
   

   2. Diamagnetism

   
   
   

   3. Ferromagnetism

   
   
   

   4. Ferrimagnetism

   
   
   

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   N/A

   Correct Option: B

   N/A

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15. Assertion (A) : In our houses, the current in AC electricity line changes direction 60 times per second.
    Reason (R): The frequency of alternating voltage supplied is 50 Hz.

1. 1. Both A and R are individually true and R is the correct explanation of A.

   
   
   

   2. Both A and R are individually true but R is not the correct explanation of A

   
   
   

   3. A is true but is false

   
   
   

   4. A is false but R is true

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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