101. Choose the correct statement

1. 1. Electric lines of force are closed curves while magnetic lines are not

   
   
   

   2. Magnetic lines of force are closed curves while electric lines are not

   
   
   

   3. Both electric and magnetic lines of force are closed curves

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: B

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102. Metals are good conductor of heat than insulator because

1. 1. Their atoms are relatively apart

   
   
   

   2. They contain free electrons

   
   
   

   3. They have reflecting surface

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: B

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103. Magnetic field due to an infinite current carrying wire varies with the distance (r) from the wire as

1. 1. r

   
   
   

   2. r²

   
   
   

   3. 1 / r

   
   
   

   4. 1 / r²

   
   
   

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   N/A

   Correct Option: C

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104. Constantan wire is used in making standard resistance because its

1. 1. Melting point is high

   
   
   

   2. Density is high

   
   
   

   3. Specific resistance is low

   
   
   

   4. Temperature coefficient of resistance is negligible

   
   
   

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   N/A

   Correct Option: D

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105. When an ebonite rod is rubbed with fur, the charge acquired by the fur is

1. 1. Negative

   
   
   

   2. Positive

   
   
   

   3. Neutral

   
   
   

   4. None of these

   
   
   

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   N/A

   Correct Option: B

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