61. A steady current is flowing is flowing in a conductor of non-uniform cross-section. The charge passing through and cross-section per unit time is

1. 1. Directly proportional to the area of cross-section

   
   
   

   2. Inversely proportional to the area of cross-section

   
   
   

   3. Proportional to square of the area of cross-section

   
   
   

   4. Independent of the area of cross-section

   
   
   

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   NA

   Correct Option: D

   NA

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62. Potentiometer measures potential more accurately because

1. 1. It measures potential in the closed circuit

   
   
   

   2. It measures potential in the open circuit

   
   
   

   3. It uses high resistance potential in the open circuit

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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63. An electric fan and heater are marked as 100 W and 220 V and 1000 W and 220 V respectively. The resistance of heater is

1. 1. Zero

   
   
   

   2. Greater than that of the fan

   
   
   

   3. Lesser than that of than

   
   
   

   4. Equal to than of fan

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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64. The filament of bulb is of

1. 1. Mercury

   
   
   

   2. Copper

   
   
   

   3. Tungsten

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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65. Two electric bulbs whose resistances are in the ratio 1 : 2 are connected in parallel to a constant voltage source. the power dissipated in them have the ratio

1. 1. 1 : 2

   
   
   

   2. 1 : 1

   
   
   

   3. 2 : 1

   
   
   

   4. 1 : 4

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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